DAT Biology Questions: 6 Free Practice Tests 2023

Are you looking for a quick way to practice what you have learned and prepare for DAT biology section?

Well, you came to the right place.

We have been working for the last several months on creating high-yield DAT Biology questions that can help anyone preparing for the DAT Biology test.

These are free DAT practice tests, no tricks or anything like that.

We want to help pre-dental students prepare for the DAT and what a better way than actually using some exam-like practice questions to test your knowledge of Biology.

By taking these DAT practice tests, you can identify areas where you need to improve, strengthen your knowledge base, and ultimately boost your DAT Biology score.

You will find below 6 DAT biology practice tests with each test having a total of 40 biology questions. The idea here is to simulate what you will be tested on when you take your DAT test.

As always, feel free to leave any feedback you have about these questions. Our goal is to improve these tests and provide more free similar practice tests.

DAT Biology Practice Test #1

1 / 40

1. The innate behavior where an animal responds to a stimulus without thought is known as:

Instinct

Fixed Action Pattern

Classical conditioning

Reflex

Imprinting

2 / 40

2. What is the euphotic zone in aquatic biomes?

The zone that is semi-irradiated with sun

The zone with strong irradiance allowing for plant survival and photosynthesis

The zone where sunlight penetrates all the way to the ocean floor

The zone where there is no light or photosynthetic species

The zone where bioluminescent species produce light

3 / 40

3. What does it mean for a species to be invasive?

The species is non-native and outcompetes native species, overtaking the ecosystem.

The species is harmful and toxic to other species.

The species is native and overtakes its own ecosystem.

The species is native and helps other species thrive.

The species is non-native but does not overrun the ecosystem.

4 / 40

4. How do vestigial structures provide evidence for evolution?

They are analogous to structures in other organisms.

They perform the same function in different organisms.

They develop as a result of use and disuse.

They serve no purpose in the organism.

They are homologous to functional structures in other organisms.

5 / 40

5. Which of the following best defines evolution?

The rapid change of traits in a single generation.

The gradual development and change of heritable traits in populations over successive generations.

The development of an individual organism over its lifetime.

The immediate adaptation of an organism to its environment.

The consistent and unchanging distribution of traits in a population.

6 / 40

6. Which of the following reproductive methods involves offspring developing and hatching outside of the mother's body?

Ovoviviparity

Oviparity

Viviparity

Hermaphroditism

Parthenogenesis

7 / 40

7. In which layer of the epidermis do keratinocyte stem cells proliferate?

Stratum basale

Stratum spinosum

Stratum granulosum

Stratum corneum

Stratum lucidum

8 / 40

8. Where are eccrine glands located?

Only in the dermis

Throughout the entire body surface

Only in the epidermis

At specific sites such as the armpits and groin

Only in the palms of the hands and soles of the feet

9 / 40

9. Which substances are almost completely reabsorbed by the nephron due to their importance in the body?

Water and salts

Na+ and Cl-

Urea and waste products

Proteins and blood cells

Glucose and amino acids

10 / 40

10. What best describes the relationship between marine fish and their environment in terms of osmoregulation?

Marine fish are hypotonic to their environment

Marine fish are hypoosmotic to their environment

Marine fish are isotonic to their environment

Marine fish are hypertonic to their environment

Marine fish are hyperosmotic to their environment

11 / 40

11. What is the role of enteropeptidase in digestion?

It digests carbohydrates to simple sugars

It activates the release of digestive enzymes from the pancreas

It digests fats to fatty acids

It digests proteins to amino acids

It converts trypsinogen to trypsin

12 / 40

12. What is the function of Antidiuretic hormone (ADH)?

It decreases water retention.

It decreases the rate of urination by increasing water retention.

It increases the rate of urination.

It has no effect on the rate of urination.

It increases the number of aquaporins for water elimination.

13 / 40

13. What type of feedback loop promotes stability in the body by preventing hormone overproduction?

Loop feedback

Negative feedback

Neither positive nor negative feedback

Positive feedback

Both positive and negative feedback

14 / 40

14. Which of the following types of cartilage is highly flexible and found in ears and epiglottis?

B and C

Elastic cartilage

A and B

Fibrous cartilage

Hyaline cartilage

15 / 40

15. What is the function of the epiphysis in a long bone?

It is the end of a long bone that forms joints with other bones.

It contains blood vessels for nutrient supply.

It is the area of fat storage within the medullary cavity.

It is a long, hollow shaft in the center of the bone.

It is a small space between lamellae that holds bone cells.

16 / 40

16. What is the deepest sheath that covers the muscle fibers?

Sarcoplasm

Epimysium

Sarcolemma

Endomysium

Perimysium

17 / 40

17. What happens when a stimulus causes the threshold potential to be reached in a neuron?

Voltage-gated K+ channels open and let K+ out of the cell

Voltage-gated Na+ channels open and let Na+ in, resulting in depolarization of the neuron

Voltage-gated Ca2+ channels open and let Ca2+ into the neuron

Both A and B

Voltage-gated Cl- channels open and let Cl- into the cell

18 / 40

18. What is the function of the myelin sheath?

To help recycle neurotransmitters

To form the blood-brain barrier

To produce cerebrospinal fluid

To receive signals from other neurons

To speed up action potential propagation

19 / 40

19. Which type of presentation involves T cells binding to antigens presented on APCs and then releasing interleukins to boost both innate immunity and adaptive immunity?

MHC II presentation

Natural presentation

Active presentation

Passive presentation

MHC I presentation

20 / 40

20. Which of the following is an example of external immunity?

Natural killer cells

Phagocytic cells

Mucous membranes

Complement proteins

Inflammatory response

21 / 40

21. What is the main intracellular buffer system in humans?

Carbonic acid buffering system

Phosphate buffering system

Hemoglobin buffering system

Carbonic anhydrase buffering system

Bicarbonate buffering system

22 / 40

22. The sinoatrial (SA) node is responsible for initiating the cardiac cycle. Which of the following statements is true about it?

It is responsible for adding a brief delay between the contraction of the atria and the contraction of the ventricles

It is located in the upper wall of the left atrium

It sends a signal to the bundle of His to initiate contraction

It is located in the lower wall of the right atrium

It is self-excitable and has the greatest automaticity

23 / 40

23. What is the correct formula for calculating cardiac output (CO)?

CO = SV x TPR

CO = HR + SV

CO = HR / SV

CO = HR x SV

CO = SV / HR

24 / 40

24. What is a characteristic feature of bryophytes?

They spend the majority of their life cycle in the sporophyte stage.

They are vascular plants.

They are found in dry habitats.

They grow vertically to remain close to water and nutrients.

They contain rhizoids which aid in water absorption and minor anchorage.

25 / 40

25. What is the first part of the embryo to emerge during the process of germination?

Epicotyl

Hypocotyl

Radicle

Plumule

Endosperm

26 / 40

26. What is the primary mode of reproduction for organisms in the Platyhelminthes phylum?

Asexual

Parthenogenesis

Sexual

Both sexual and asexual

Budding

27 / 40

27. How are DNA microarrays used in genomics research?

To identify the location of genes on a chromosome.

To determine which genes are being expressed.

To replicate DNA sequences.

To store genomic information.

To sequence the genome of a new species.

28 / 40

28. What is the correct order of organelles from most dense to least dense in density centrifugation?

Nuclei > ER fragments > mitochondria/chloroplast > ribosomes

Nuclei > mitochondria/chloroplast > ER fragments > ribosomes

ER fragments > mitochondria/chloroplast > ribosomes > nuclei

Mitochondria/chloroplast > ER fragments > nuclei > ribosomes

Ribosomes > ER fragments > mitochondria/chloroplast > nuclei

29 / 40

29. What is an example of polygenic inheritance?

ABO blood typing

Red and white flowers producing pink offspring

Baldness gene covering up the genes for hair color

Height, a single trait affected by many genes

Cystic fibrosis with multiple symptoms caused by a single gene

30 / 40

30. What is the definition of heredity?

The process of DNA replication

The passing of traits from parents to offspring

The genetic composition of an organism

The observable traits that result from a genotype

The process of protein synthesis

31 / 40

31. In the structure of nucleosomes, which histone holds the DNA in place?

Histone H1

Histone H4

Histone H2B

Histone H3

Histone H2A

32 / 40

32. What are the sister chromatids in a dyad connected by?

Sex chromosomes

Centromeres

Microtubules

Autosomes

Kinetochores

33 / 40

33. What is the function of the pericentriolar material?

To check DNA for any errors after replication

To pull sister chromatids apart during cell division

To separate sister chromatids in a dyad

To guide chromosomes during karyokinesis

To start microtubule extension

34 / 40

34. What occurs during the process of non-cyclic photophosphorylation?

Only photosystem II is used.

Only photosystem I is used.

ATP is produced, and NADPH is not generated.

The Calvin cycle is activated.

ATP and NADPH are both generated.

35 / 40

35. Which cells in the leaf structure are responsible for most of the photosynthesis?

Stomata

Epidermal cells

Guard cells

Palisade mesophyll cells

Spongy mesophyll cells

36 / 40

36. What is the purpose of the electron transport chain in oxidative phosphorylation?

To convert ADP to ATP directly

To reduce NADH to NAD+

To pump protons into the mitochondrial matrix

To produce CO2 as a byproduct

To regenerate electron carriers and create an electrochemical gradient to power ATP production

37 / 40

37. What is the main difference between the structures of eukaryotic and prokaryotic flagella?

Prokaryotic flagella are produced by a basal body, while eukaryotic flagella are not.

Eukaryotic flagella are composed of polymers of flagellin, while prokaryotic flagella are made of polymers of tubulin.

Prokaryotic flagella are composed of polymers of flagellin and do not have a 9+2 array, while eukaryotic flagella do have this 9+2 array.

Eukaryotic flagella have nine doublets of microtubules, while prokaryotic flagella have a 9+2 array.

Eukaryotic flagella move in a rotary motion, while prokaryotic flagella move in a bending motion.

38 / 40

38. What is the main difference between an agonist and an antagonist in cell signaling?

An agonist is a glycoprotein, while an antagonist is not.

An agonist decreases the fluidity of the cell membrane, while an antagonist increases it.

An agonist binds to receptors and activates a target function, while an antagonist prevents other molecules from binding.

An agonist binds to adhesion proteins, while an antagonist binds to recognition proteins.

An agonist introduces kinks in the lipid bilayer, while an antagonist does not.

39 / 40

39. Which of the following is a exception to the central dogma of genetics?

RNA → proteins → DNA

RNA → DNA → proteins

Proteins → RNA → DNA

DNA → RNA → proteins

DNA → proteins → RNA

40 / 40

40. Which of the following is not a component of carbohydrates?

Hydrogen

Carbon

All of the above are components of carbohydrates

Nitrogen

Oxygen

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DAT Biology Practice Test #2

1 / 40

1. What is the term for the behavior used to protect an animal's territory or safe space?

Altruistic behavior

Territoriality

Sexual selection

Agonistic behavior

Search images

2 / 40

2. Who are the primary consumers in an ecosystem?

Organisms at the top of the food chain, preying on secondary consumers.

Organisms that consume dead or decaying organic material.

Organisms that generate their own food through photosynthesis.

Carnivores that prey on herbivores.

Organisms just above the producers in the food chain, often herbivores.

3 / 40

3. What role do decomposers play in an ecosystem?

They prey on two species simultaneously.

They undergo photosynthesis to generate energy.

They eat other consumers.

They compete with other species for mutual resources.

They break down and recycle dead plant or animal material.

4 / 40

4. What does "anagenesis" describe in evolutionary biology?

The splitting apart of evolutionary lineages

The process of different phenotypes becoming isolated within the same area

The gradual evolution of an interbreeding population without splitting

The process of unrelated species adapting to similar environments

The process of two species imparting selective pressure on each other

5 / 40

5. According to the theory of punctuated equilibrium, how does evolution occur?

By short spurts of evolutionary changes during periods of stasis

Due to a variety of phenotypes within a population

Slowly and gradually via accumulation of small intermediary changes

Through continuous adaptation of species to their environments

Rapidly during periods of stasis

6 / 40

6. What is the function of the notochord during neurulation?

It forms the vertebrae and skeletal muscles associated with axial skeleton.

It stimulates ectoderm to thicken, forming the neural plate.

It differentiates into the Central Nervous System (CNS).

It forms the neural crest cells.

It forms the neural tube.

7 / 40

7. Which type of gland is not found in the palms of hands and soles of feet?

Sweat gland

None of the above

Apocrine gland

Eccrine gland

Sebaceous gland

8 / 40

8. What is the function of the hypodermis?

It is the main site for fat storage

It protects against UV radiation

It synthesizes vitamin D

It generates hair follicles

It produces sweat for thermoregulation

9 / 40

9. Which of the following best describes the role of renin in the Renin Angiotensin Aldosterone System (RAAS)?

It is an enzyme that acts on angiotensinogen to activate it to the form angiotensin I.

It stimulates additional aldosterone release from the adrenal gland cortex.

It increases Na+ reabsorption from the proximal tubule.

It is a potent systemic vasoconstrictor.

It stimulates the sympathetic nervous system.

10 / 40

10. Where does filtration primarily occur in the nephron?

Loop of Henle

Proximal convoluted tubule

Collecting duct

Distal convoluted tubule

Glomerulus and the Bowman’s capsule

11 / 40

11. How does the liver handle the dangerous byproduct of protein metabolism, ammonia?

It converts ammonia into albumin

It converts ammonia into glycogen

It converts ammonia into urea

It converts ammonia into glucose

It converts ammonia into bilirubin

12 / 40

12. In females, which hormone during the menstrual cycle causes ovulation?

Estrogen

Testosterone

Progesterone

FSH

13 / 40

13. The hormone FSH in males stimulates what?

Fight or flight response

Blood glucose level increase

Sperm maturation

Testosterone production

Glucose storage

14 / 40

14. Which of the following hormones increases blood calcium levels by stimulating osteoclasts and depressing osteoblasts?

Growth hormone

Parathyroid hormone

Vitamin D

Calcitonin

Thyroid hormone

15 / 40

15. What is the function of the epiphyseal plate?

To provide support for the body

To contain red bone marrow for hematopoiesis

To provide protection for the organs

To lengthen the diaphysis through growth and ossification

To store fat in the medullary cavity

16 / 40

16. Which of the following statements accurately describes the I band?

The I band is the area in the sarcomere where only actin filaments are present.

The I band is the midpoint of the sarcomere.

The I band is the area in the sarcomere where only thin actin filaments are present.

The I band is the area in the sarcomere where only myosin filaments are present.

The I band is the area in the sarcomere where actin and myosin overlap.

17 / 40

17. What type of cells form the myelin sheath in the peripheral nervous system?

Astrocytes

Schwann cells

Ependymal cells

Satellite cells

Oligodendrocytes

18 / 40

18. Which neurotransmitter is associated with the "fight or flight" response?

Norepinephrine

Dopamine

Acetylcholine

GABA

Serotonin

19 / 40

19. Which type of immunity is responsible for the production and release of antibodies?

Cell-mediated immunity

Passive immunity

Humoral immunity

Artificial immunity

Innate immunity

20 / 40

20. Which type of leukocyte is responsible for the first part of the inflammatory response?

Natural killer cells

Mast cells

B cells

Neutrophils

T cells

21 / 40

21. Which of the following is NOT a component of the bicarbonate buffering system?

Carbon dioxide

Hemoglobin

Carbonic acid

Water

Bicarbonate anion

22 / 40

22. What is the primary function of the umbilical vein in fetal circulation?

Carries deoxygenated blood from the fetus to the placenta

Connects the pulmonary artery to the aorta

Connects the umbilical vein to the inferior vena cava

Carries oxygenated blood from the placenta to the fetus

Allows oxygen-poor blood to leave the pulmonary artery

23 / 40

23. Which of the following statements is true about blood clotting?

A clot is formed before platelets aggregate

Platelets release thromboplastin to attract more platelets

It is an example of a negative feedback mechanism

Fibrinogen is an active form that forms the clot

Exposed collagen triggers platelet activation

24 / 40

24. What is the role of auxins in plant growth?

They regulate cell differentiation and division.

They cause cell growth and are responsible for plant tropisms.

They are responsible for stem and shoot elongation.

They function during stress and inhibit growth.

They increase fruit ripening.

25 / 40

25. Which type of growth occurs at the apical meristems and leads to vertical growth in plants?

Tertiary growth

Secondary growth

Initial growth

Primary growth

Terminal growth

26 / 40

26. Which type of chordate lacks a heart in its circulatory system?

Reptilia

Tunicates

Lancelets

Fish (Bony)

Mammalia (Monotremes)

27 / 40

27. What does the term "competent" mean in the context of bacterial cloning?

The bacteria can be easily stained

The bacteria can undergo transformation

The bacteria have a high growth rate

The bacteria are resistant to antibiotics

The bacteria can be easily viewed under a microscope

28 / 40

28. What is the process of creating millions of copies of DNA called?

Polymerase Chain Reaction (PCR)

CRISPR

Gel electrophoresis

Bacterial cloning

Karyotyping

29 / 40

29. Which term refers to a sequence of DNA that codes for a trait?

Mutation

Gene

Allele

Genome

Locus

30 / 40

30. What is the difference between incomplete dominance and codominance?

Incomplete dominance has an intermediate state, while codominance expresses both alleles

Incomplete dominance expresses both alleles, while codominance has an intermediate state

Incomplete dominance has multiple allele options, while codominance does not

Incomplete dominance is when many genes are responsible for one trait, while codominance is when one gene is responsible for many traits

Incomplete dominance is when one gene affects the expression of another, while codominance is when one gene is responsible for many traits

31 / 40

31. What is the primary difference between the action of exonucleases and endonucleases on a polynucleotide chain?

Exonucleases cleave nucleotides from the ends of the chain, while endonucleases cleave from the inside of the chain.

Exonucleases add nucleotides to the ends of the chain, while endonucleases add nucleotides to the inside of the chain.

Exonucleases aid in transcription, while endonucleases aid in translation.

Exonucleases remove the 5' cap, while endonucleases remove the poly A tail.

Exonucleases cleave nucleotides from the inside of the chain, while endonucleases cleave from the ends of the chain.

32 / 40

32. What happens during the G0 phase of the cell cycle?

The cell divides into two daughter cells.

The cell prepares for cell division by checking DNA for any errors after replication.

The cell replicates its genome.

The cell checks for favorable conditions and, if unfavorable, it halts in the cell cycle.

The cell grows in preparation for cell division.

33 / 40

33. What happens in the prophase of mitosis?

Chromatin condenses into chromosomes

The physical separation of the cytoplasm and cell membrane into two daughter cells

etochore microtubules shorten to pull sister chromatids apart

The spindle apparatus guides the chromosomes to the metaphase plate

Chromosomes have segregated and nuclear membranes reform

34 / 40

34. What is the main drawback in the process of C4 photosynthesis?

The production of excess glucose.

The release of CO2 in the mesophyll cells.

The production of pyruvate that needs to be shuttled back to mesophyll cells using ATP energy.

The production of excess oxygen.

The spatial isolation of carbon dioxide.

35 / 40

35. In which part of the plant cell does the Calvin cycle take place?

Thylakoid membrane

Cytoplasm

Chloroplast stroma

Mitochondria

Nucleus

36 / 40

36. In the Cori cycle, where does lactate get transported to be converted back into glucose?

Mitochondria

Muscle cells

Kidneys

Red blood cells

Liver cells

37 / 40

37. What is the term used to describe the process by which a cell's cytoplasm shrinks away from the cell wall due to water loss from being in a hypertonic solution?

Plasmolysis

Hyperplasia

Dysplasia

Atrophy

Hypertrophy

38 / 40

38. Which factor affects the fluidity of the cell membrane?

The temperature and level of cholesterol and unsaturation of fatty acids

The size of the hydrocarbon rings in cholesterol

The level of membrane protein saturation

The presence of adhesion proteins

The presence of carbohydrate chains

39 / 40

39. What nitrogenous base is found in RNA instead of thymine?

Uracil (U)

Adenine (A)

Cytosine (C)

Thymine (T)

Guanine (G)

40 / 40

40. What is the empirical formula of monosaccharides?

(CH2O)n

CH4O2

CHO

C2H4O2

C6H12O6

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DAT Biology Practice Test #3

1 / 40

1. Which type of mating involves mating once in a lifetime and producing multiple offspring without parental care?

Polygyny

Polygamy

Semelparity

Monogamy

Polyandry

2 / 40

2. Which of the following behaviors is most accurately classified as a Fixed Action Pattern?

A bird migrating in response to seasonal changes.

Ducklings following a moving object, believing it to be their mother.

A flatworm increasing its speed when exposed to light.

An animal responding to a stimulus more frequently as the stimulus occurs more often.

A goose rolling an egg back into its nest.

3 / 40

3. What happens to the energy stored in a trophic level as it is transferred to the next trophic level?

It is equally distributed among all the organisms in the next trophic level.

All of it is transferred to the next trophic level.

Approximately 90% of it is converted to organic tissue in the next trophic level.

All of it is lost as heat.

Only about 10% of it is converted to organic tissue in the next trophic level.

4 / 40

4. What does a cladogram represent?

The genetic drift in a population

The inferred evolutionary relationships among various biological species

The accumulation of small intermediary changes in a species

The inherited traits of a species

The genetic variation within a population

5 / 40

5. Which of the following is not an example of prezygotic isolation?

Behavioral Isolation

Temporal Isolation

Habitat Isolation

Mechanical Isolation

Hybrid Sterility

6 / 40

6. Regarding stem cells, which of the following is the correct sequence from most potent to least potent?

Multipotent, Totipotent, Pluripotent

Totipotent, Pluripotent, Multipotent

Pluripotent, Totipotent, Multipotent

Pluripotent, Multipotent, Totipotent

Multipotent, Pluripotent, Totipotent

7 / 40

7. Which of the following accurately describes binary fission?

A bud forms on the organism, and DNA is replicated and deposited into the bud.

An unfertilized egg develops into a viable organism.

Germ cells produce gametes via meiosis.

DNA is replicated and migrates to opposite ends of the cell, and then the cell separates into two.

A piece of the organism breaks off, and it can regenerate the broken piece.

8 / 40

8. Which layer of the epidermis is important for strength and immunity?

Granulosum

Basale

Lucidum

Corneum

Spinosum

9 / 40

9. What is the primary function of Atrial natriuretic peptide (ANP) when released by atrial cells?

It is a potent systemic vasoconstrictor.

It causes aquaporins to insert into the collecting duct of the nephron.

It reduces blood volume and blood pressure.

It increases Na+ reabsorption from the proximal tubule.

It stimulates additional aldosterone release from the adrenal gland cortex.

10 / 40

10. What is the primary force driving filtration in Bowman’s capsule?

Gravity

Hydrostatic pressure from the blood

Passive transport

Osmotic pressure

Active transport

11 / 40

11. What does the liver do when glycogen stores are depleted?

Glycogenesis

Detoxification

Hormone synthesis

Gluconeogenesis

Protein synthesis

12 / 40

12. Which of the following best describes the role of pseudopodia in amoebas?

They are temporary protrusions used for cell movement and feeding.

They are used for extracellular digestion.

They form the amoeba's cell wall.

They allow the amoeba to communicate with other cells.

They aid in the amoeba's movement.

13 / 40

13. What does the hormone aldosterone function to do?

Decrease blood volume and blood pressure

Increase blood glucose levels

Regulate the menstrual cycle

Decrease blood glucose levels

Increase blood volume and blood pressure

14 / 40

14. Which of the following cell types is responsible for bone resorption during bone remodeling?

Monocytes

Osteoclasts

Osteocytes

Osteoprogenitors

Osteoblasts

15 / 40

15. What is the function of cancellous bone?

To synthesize blood cells

To provide protection for the organs

To soak up red bone marrow via a web of trabeculae

To support the weight of the body

To store fat in the medullary cavity

16 / 40

16. Which of the following types of motor units is used for powerful movements?

None of the above

Small motor units with a low ratio of motor neurons to muscle fibers

Small motor units with a high ratio of motor neurons to muscle fibers

Large motor units with a high ratio of motor neurons to muscle fibers

Large motor units with a low ratio of motor neurons to muscle fibers

17 / 40

17. Which of the following statements is true regarding the sliding filament theory of muscle contraction?

The sarcoplasmic reticulum releases calcium ions into the sarcomere through ligand-gated calcium channels.

Troponin removes tropomyosin from the actin-binding sites, allowing actin and myosin to bind.

Graded potentials are produced by the opening of voltage-gated calcium channels.

Actin and myosin filaments contract independently of each other.

Myofilaments slide past each other to shorten sarcomeres.

18 / 40

18. Which neurotransmitter is associated with reward, pleasure, and addiction?

GABA

Dopamine

Acetylcholine

Serotonin

Norepinephrine

19 / 40

19. What is the function of platelets in the innate immune system?

To produce histamine

To attack virally-infected cells

To regulate macrophages and dendritic cells

To kill parasites

To neutralize pathogens that have entered the body

20 / 40

20. Which type of leukocyte makes up over half of all leukocytes?

T cells

Basophils

Eosinophils

B cells

Neutrophils

21 / 40

21. Which of the following is NOT a reason for a left-shifted oxygen dissociation curve?

Low partial pressure of carbon dioxide

Fetal hemoglobin

Increased body temperature

Increased pH

All of the above are reasons for a left-shifted curve

22 / 40

22. Which of the following is true about respiration in Cnidaria?

They use slimy mucus to facilitate the transport of oxygen into their open circulatory system.

They have gills

Gas exchange happens mainly through the tracheal system

They use simple diffusion

They have a closed circulatory system

23 / 40

23. Which type of blood can receive blood from any donor?

Type O

None of the above

Type AB

Type B

Type A

24 / 40

24. What is the function of the Casparian strip in the roots of plants?

It forces water coming from the cell walls into the cytoplasm for filtering.

It increases the surface area of roots for greater nutrient and water uptake.

It prevents the growth of roots.

It aids in photosynthesis.

It facilitates the movement of water from soil into the roots.

25 / 40

25. Which type of cell in the xylem allows for water transport through pits in their tapered ends?

Vessel elements

Companion cells

Tracheids

Sieve cells

Parenchyma cells

26 / 40

26. Which of the following chordates have a two-chambered heart?

Fish (Cartilaginous)

Reptilia

Birds

Mammalia (Placental)

Mammalia (Monotremes)

27 / 40

27. What is the primary distinguishing feature between prokaryotes and eukaryotes?

The process of DNA replication

Ability to produce endospores

Membrane-bound organelles

Presence of ribosomes

Cell wall

28 / 40

28. What type of blotting is used to identify fragments of known RNA?

Western blotting

Southern blotting

Eastern blotting

Northern blotting

DNA

29 / 40

29. What does the term "heterozygous" mean?

Only one allele is present

One copy of the gene is lost or nonfunctional

Two different copies of the same chromosome

One dominant allele and one recessive allele in a homologous pair

The same allele in both homologs

30 / 40

30. What is the role of proto-oncogenes in cancer development?

They inhibit phosphorylation activity

They suppress cancerous growth

They become oncogenes due to gain-of-function mutations

They prevent cells from becoming cancerous

They cause cancer due to loss-of-function mutations

31 / 40

31. Which of the following is not a potential outcome of base substitutions (point mutations) in DNA?

Silent mutations

Nonsense mutations

All are potential outcomes of base substitutions.

Missense mutations

Frameshift mutations

32 / 40

32. How does acetylation of histones affect gene transcription?

It increases transcription by relaxing DNA-histone attractions.

It randomly increases or decreases transcription.

It decreases transcription by loosening DNA-histone attractions.

It increases transcription by tightening DNA-histone attractions.

It does not affect gene transcription.

33 / 40

33. What distinguishes meiosis I from meiosis II?

Meiosis I involves separation of sister chromatids, while meiosis II involves separation of homologous chromosomes.

Meiosis I results in four daughter cells, while meiosis II results in two daughter cells.

Meiosis I is a reductional division, while meiosis II is an equational division.

Meiosis I begins with a haploid cell, while meiosis II begins with a diploid cell.

Meiosis I only occurs in animals, while meiosis II only occurs in plants.

34 / 40

34. What is the primary function of RuBisCo in the process of photosynthesis?

It facilitates the fixation of carbon dioxide into RuBP.

It helps in the creation of ATP.

It aids in the process of photolysis.

It converts oxygen into carbon dioxide.

It helps in the transportation of water in the plant.

35 / 40

35. What is the main difference between C4 photosynthesis and CAM photosynthesis?

C4 photosynthesis occurs only in hot environments, while CAM photosynthesis occurs in all environments.

C4 photosynthesis and CAM photosynthesis are the same process.

C4 photosynthesis uses spatial isolation of carbon dioxide, while CAM photosynthesis uses temporal isolation.

C4 photosynthesis is not used by any plants, while CAM photosynthesis is used by all plants.

C4 photosynthesis uses temporal isolation of carbon dioxide, while CAM photosynthesis uses spatial isolation.

36 / 40

36. Alcohol fermentation includes an extra step compared to lactic acid fermentation. What does this step involve?

The oxidation of pyruvate into lactic acid

The decarboxylation of pyruvate into acetaldehyde

The conversion of acetaldehyde into ethanol

The reduction of pyruvate into acetaldehyde

The conversion of NADH to NAD+

37 / 40

37. What is the key difference between catabolic and anabolic processes in an organism's metabolism?

Catabolic processes consume energy while anabolic processes produce energy.

Anabolic processes involve breaking down larger molecules for energy while catabolic processes involve using energy to build larger macromolecules.

Anabolic processes consume oxygen while catabolic processes do not require oxygen.

Catabolic processes involve breaking down larger molecules for energy while anabolic processes involve using energy to build larger macromolecules.

Catabolic processes involve the synthesis of ATP while anabolic processes involve the breakdown of ATP.

38 / 40

38. Which of the following best describes the role of the sodium-potassium pump in the cell?

It is a type of active transport that uses ATP hydrolysis to pump molecules against their concentration gradient.

It is a type of passive diffusion that uses a carrier protein to bring molecules down their concentration gradient.

It is a type of secondary active transport that uses the energy released when other molecules flow down their concentration gradient.

It is a type of simple diffusion that allows small, uncharged molecules to flow down their concentration gradient.

It is a type of facilitated transport that uses a channel protein to allow ions to flow down their concentration gradient.

39 / 40

39. Which of the following statements is NOT part of modern cell theory?

Genetic information is stored and passed down through DNA.

An organism’s activity is dependent on the total activity of its independent cells.

The cell is the basic structural, functional, and organizational unit of life.

All cells come from non-living matter.

All lifeforms have one or more cells.

40 / 40

40. What is the difference between amylose and amylopectin?

Amylose is a monosaccharide while amylopectin is a disaccharide

Amylose is linear while amylopectin is branched

Amylose is branched while amylopectin is linear

Amylose contains glucose and fructose, while amylopectin contains only glucose

There is no difference between amylose and amylopectin

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DAT Biology Practice Test #4

1 / 40

1. Which term refers to a behavior where one animal's threat causes another animal's submission, thus preventing aggression?

Territoriality

Cooperative hunting

Reciprocal altruism

Dominance Hierarchy

Appeasement behavior

2 / 40

2. A behavioral response that decreases in response to a repetitive, meaningless stimulus is known as:

Recovery

Habituation

Extinction

Stimulus generalization

Sensitization

3 / 40

3. What is the principle of Malthus's population theory?

Population increases arithmetically while food production increases geometrically

Population increases geometrically while food production increases exponentially

Population and food production both increase arithmetically

Population and food production both increase geometrically

Population increases geometrically while food production increases arithmetically

4 / 40

4. What is the result of sympatric speciation?

Species are reproductively isolated via prezygotic and postzygotic isolating mechanisms

Different phenotypes are isolated within the same area

Species arise from one ancestor as they adapt differently to their environments

Species diverge due to a geographical barrier

Species evolve to resemble another species

5 / 40

5. What is a 'polytomy' in the context of a phylogenetic tree?

The splitting apart of evolutionary lineages

The gradual evolution of an interbreeding population without splitting

An ancestor and some but not all of its descendants

An internal node of a phylogenetic tree that leads to more than two tips

An ancestor and all its descendants

6 / 40

6. What is the role of the mesoderm layer in a trilaminar embryo?

It forms the bone and skeleton, muscles, cardiovascular system, and gonads

It forms the sensory parts of the ear, eye, and nose

It forms the epithelial lining of the digestive, respiratory, and excretory systems

It forms the pigmentation cells and the enamel of teeth

It forms the Central Nervous System (CNS) and Peripheral Nervous System (PNS)

7 / 40

7. Which hormone is responsible for the maturation of sperm and the development of male secondary sex characteristics?

Progesterone

Estrogen

Luteinizing Hormone (LH)

Testosterone

Follicle Stimulating Hormone (FSH)

8 / 40

8. What are the two layers of the dermis?

Papillary dermis and cornified dermis

Basal dermis and spinous dermis

Papillary dermis and reticular dermis

Lucid dermis and reticular dermis

Papillary dermis and granular dermis

9 / 40

9. What occurs as the filtrate travels down the descending limb of the loop of Henle?

Filtrate becomes less concentrated

Filtrate becomes more alkaline

Na+ and Cl- are reabsorbed

Solutes are reabsorbed

Water is reabsorbed into the blood

10 / 40

10. How does the length of the nephron affect the concentration of urine?

The shorter the nephron, the more diluted the urine will be

The length of the nephron has no effect on urine concentration

The longer the nephron, the more concentrated the urine will be

The shorter the nephron, the more concentrated the urine will be

The longer the nephron, the more diluted the urine will be

11 / 40

11. Which hormone is responsible for slowing gastric emptying and stimulating the release of digestive enzymes and bile?

Gastrin

Glucagon

Cholecystokinin (CCK)

Secretin

Insulin

12 / 40

12. What is the primary function of G cells in the stomach during digestion?

They secrete gastric lipase and pepsinogen.

They produce the basic bicarbonate ions that neutralize stomach acid.

They facilitate mechanical digestion through the churning of food.

They produce mucus to protect the stomach lining.

They release gastrin, a hormone that stimulates the release of gastric juice and the secretion of enzymes.

13 / 40

13. Which of the following is the most common cause of goiter?

Iodine deficiency

High blood calcium levels

Excessive secretion of parathyroid hormone (PTH)

Hypothyroidism

Hyperthyroidism

14 / 40

14. Which type of bone is found within tendons to help muscles pull?

Irregular bones

Short bones

Flat bones

Sesamoid bones

Long bones

15 / 40

15. What is the function of Volkmann's canals?

To provide support for the body

To store fat in the medullary cavity

To connect the haversian canals to the periosteum

To connect lacunae and the haversian canal

To synthesize blood cells

16 / 40

16. Which of the following statements accurately describes the process of wave summation?

Wave summation is the process by which different motor units are stimulated at different times to produce the intended amount of muscle contraction.

Wave summation occurs when a depolarization is below threshold potential.

Wave summation occurs when a depolarization is above threshold potential.

Wave summation is the process by which twitches add up to create a larger overall contraction.

Wave summation is also known as the size principle of motor unit recruitment.

17 / 40

17. Which type of muscle is characterized by involuntary contractions?

Cardiac muscle

Both smooth and cardiac muscle

Skeletal muscle

Smooth muscle

None of the above

18 / 40

18. Which part of the ear helps convert mechanical signals into neuronal signals?

Outer ear

Round window

Inner ear

Semicircular canal

Middle ear

19 / 40

19. Which type of T cell is responsible for directly killing infected cells?

Natural killer cells

Helper T cells

Memory T cells

CD8 T cells

CD4 T cells

20 / 40

20. Which of the following is NOT a sign of inflammation?

Loss of function

Increased heat

Swelling

Redness

Numbness

21 / 40

21. Which of the following is true about carbon monoxide (CO) poisoning?

It increases oxygen binding affinity

It produces carboxyhemoglobin (HbCO2)

It does not affect oxygen transport efficiency

It produces carboxyhemoglobin (HbCO).

It results from oxygen outcompeting CO for hemoglobin binding

22 / 40

22. What is the difference between the left and right lungs in humans?

The left lung is larger and has three lobes, while the right lung is smaller and has two lobes

The left and right lungs are identical in size and shape.

The left lung is smaller and has one lobe, while the right lung is larger and has two lobes

The left lung is smaller and has two lobes, while the right lung is larger and has three lobes

The left lung is larger and has two lobes, while the right lung is smaller and has one lobe

23 / 40

23. What is erythroblastosis fetalis?

A condition where the mother’s Rh factor is negative

A condition where the mother’s body attacks the fetus because of a blood type mismatch

A condition where the placenta does not function properly

A condition where the fetus is unable to produce red blood cells

A condition where the fetus’ blood type is AB

24 / 40

24. Which theory explains the upward movement of water in plants due to transpiration?

Source to Sink theory

Root pressure theory

Capillary action

Cohesion-tension theory

Pressure flow hypothesis

25 / 40

25. What type of plant tissue provides protection and regulation and includes the epidermis and root hairs?

Ground tissue

Vascular tissue

Cambium tissue

Dermal tissue

Stomatal tissue

26 / 40

26. Which phylum is characterized by five-fold radial symmetry as adults?

Echinodermata

Mollusca

Arthropoda

Annelida

Cnidaria

27 / 40

27. What is the main difference between gram-positive and gram-negative bacteria?

The staining color in gram staining

The thickness of the peptidoglycan layer

The presence of a peptidoglycan layer

The presence of an outer membrane

The ability to secrete exotoxins

28 / 40

28. What is the purpose of a genomic library?

To store the RNA of an organism's genome.

To facilitate the replication of an organism's genome.

To store the DNA of an organism's genome.

To store all known species' genomes.

To identify the protein structures of an organism.

29 / 40

29. What does gene linkage refer to?

Genes that are found close together on the same chromosome.

The process where two genes are randomly assorted in progeny.

The process of crossing over during prophase I of meiosis.

The process where two organisms are mated to produce offspring.

The process where a single gene is examined through two generations of crosses.

30 / 40

30. What is the one-hit hypothesis associated with?

Retinoblastoma gene

Null alleles

Proto-oncogenes

Tumor-suppressor genes

Incomplete penetrance

31 / 40

31. What is the purpose of the G1/S checkpoint in the cell cycle?

It ends DNA replication when the replication fork cannot continue.

It induces transcription of genes.

It regulates cell cycle transition from the G1 phase into the S phase, checking for favorable conditions to grow.

It regulates the termination of transcription.

It initiates DNA replication.

32 / 40

32. In which direction does RNA polymerase extend the RNA during transcription?

Both a and b

5’ → 5’

5’ → 3’

3’ → 5’

3’ → 3’

33 / 40

33. In terms of regulation, what is the role of cyclin-dependent kinases (CDKs) in the cell cycle?

They act as checkpoints to assess DNA replication accuracy and MPF levels.

They prevent cells from dividing unless attached to an external surface.

They phosphorylate certain substrates to signal cell cycle progression.

They bind to receptors in the plasma membrane to signal for cell division.

They halt cell division when the density of cells is high.

34 / 40

34. What is the primary difference between C4 and CAM photosynthesis?

CAM photosynthesis uses temporal isolation of carbon dioxide, while C4 uses spatial isolation.

CAM photosynthesis uses spatial isolation of carbon dioxide, while C4 uses temporal isolation.

C4 photosynthesis involves the production of a four-carbon molecule, while CAM does not.

C4 photosynthesis occurs in plants living in hot environments, while CAM occurs in plants living in cold environments.

There is no significant difference between C4 and CAM photosynthesis.

35 / 40

35. What is the role of chlorophyll in the photosynthesis process?

Chlorophyll is responsible for the release of oxygen.

Chlorophyll is involved in carbon fixation.

Chlorophyll is responsible for the conversion of glucose to ATP.

Chlorophyll is not involved in the photosynthesis process.

Chlorophyll is involved in the absorption of photons.

36 / 40

36. What function do High-density lipoproteins (HDLs) serve in the body?

They help release triglycerides back into circulation

They store triglycerides

They convert triglycerides into free fatty acids

They transport cholesterol to the liver to make bile

They transport cholesterol to peripheral tissues

37 / 40

37. Why is ATP considered the cellular energy currency?

It contains an adenine nitrogenous base.

It is more stable than ADP.

It has high energy bonds between the phosphate groups that release energy upon hydrolysis.

It is used to fuel all cellular processes.

It contains three phosphate groups.

38 / 40

38. What role does clathrin play in the transport of substances across the cell membrane?

It aids in facilitated transport by acting as a channel protein.

It aids in exocytosis by allowing vesicles to secrete material into the extracellular environment.

It aids in endocytosis by forming a pit in the membrane that pinches off as a coated vesicle.

It aids in active transport by using ATP hydrolysis to pump molecules against their concentration gradient.

It aids in simple diffusion by allowing small, uncharged substances to cross the cell membrane.

39 / 40

39. Which of the following statements is true about catalysts?

They shift a chemical reaction to the left

They increase the spontaneity of a reaction

They raise the activation energy of a reaction

They affect the transition state of a reaction

They do not affect the energy of the transition state

40 / 40

40. What is the definition of an element?

A pure substance that has specific physical/chemical properties and can’t be broken down into a simpler substance.

A mixture of two or more elements.

A mixture of two or more compounds.

A pure substance that has specific physical/chemical properties and can be broken down into a simpler substance.

A pure substance that has no physical/chemical properties.

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DAT Biology Practice Test #5

1 / 40

1. What does the concept of "inclusive fitness" refer to?

Maximizing the quantity of offspring

Grouping together to achieve a goal

Abbreviating what food looks like to locate it quickly

Sacrifices made for relatives

Maximizing the quality of mates and offspring

2 / 40

2. In the context of animal behaviors, what does the term "stimulus discrimination" mean?

Differentiation between a conditioned stimulus and other similar, but different, non-conditioned stimuli.

As a stimulus occurs more often, the behavioral response increases.

Learning to associate a behavior with a reward.

The behavior of an animal changing speed in random directions in response to environmental conditions.

Decreasing behavioral response in response to repetitive, meaningless stimulus.

3 / 40

3. Which of the following correctly represents the type II survivorship curve?

Organism derives its energy from inorganic compounds and uses organic compounds as its primary carbon source

Organism derives its energy from light and uses CO2 as its primary carbon source

Survival probability is constant regardless of age

Long gestation period, few, large offspring, long time to mature, significant parental investment

Abundant, small offspring, mature quickly, no parental investment

4 / 40

4. What is the type of symbiosis where one organism benefits and the other organism is unaffected?

Predation

Allelopathy

Mutualism

Commensalism

Parasitism

5 / 40

5. In terms of genetic variation, what does "balanced polymorphism" refer to?

The combination of gametes in sexual reproduction

The process of outbreeding in a population

The maintenance of a variety of phenotypes within a population

A high mutation rate within a population

The presence of multiple copies of alleles in plant species

6 / 40

6. Which of the following correctly describes the process of capacitation in sperm cells?

It is the process by which the sperm cell fuses with the egg cell during fertilization

It is the final maturation step for sperm prior to fertilization, triggered by secretions in the uterine wall

It is the initial formation of sperm cells in the testes

It is the division of a sperm cell into two haploid cells

It is the process by which the sperm cell enters the zona pellucida of the egg cell

7 / 40

7. In the context of birth control pills, how does the release of synthetic estrogen and progesterone prevent pregnancy?

By promoting the development of follicles in the ovary.

By stimulating the formation of corpus luteum.

By causing a rapid LH spike leading to ovulation.

By inhibiting GnRH production during the menstrual cycle through negative feedback.

By causing uterine contractions which propel sperm.

8 / 40

8. What are the three possible shapes for epithelial cells?

Columnar, cuboidal, and spherical

Squamous, cuboidal, and columnar

Rhomboidal, squamous, and cuboidal

Cuboidal, squamous, and trapezoidal

Cuboidal, hexagonal, and pyramidal

9 / 40

9. What are the three layers of the integumentary system?

Epidermis, endodermis, and hypodermis

Epidermis, mesodermis, and endodermis

Dermis, endodermis, and hypodermis

Epidermis, dermis, and endothelium

Epidermis, dermis, and hypodermis

10 / 40

10. Which hormone is produced by the adrenal cortex and increases salt and water reabsorption and potassium secretion in the distal tubules and collecting ducts?

Atrial natriuretic peptide (ANP)

Aldosterone

Renin

Angiotensin II

Antidiuretic Hormone (ADH)

11 / 40

11. What is a key indicator of the health of the microbiome in the large intestine?

The level of urea

The number of erythrocytes

Bile acid metabolism

The level of glucose

The level of glycogen

12 / 40

12. What is the primary function of bile in the digestive process?

It stimulates the secretion of digestive enzymes from the pancreas.

It neutralizes stomach acid to prevent damage to the small intestine.

It breaks down proteins into amino acids.

It emulsifies fats, aiding in their absorption.

It facilitates mechanical digestion by helping to churn food in the stomach.

13 / 40

13. Which of the following hormones is secreted by the parafollicular cells in the thyroid gland?

Thyroxine (T4)

Triiodothyronine (T3)

Parathyroid hormone (PTH)

Calcitonin

Thyroid-stimulating hormone (TSH)

14 / 40

14. Which of the following hormones are derived from cholesterol?

None of the above

All of the above

Amino-acid derived hormones

Steroid hormones

Peptide hormones

15 / 40

15. Which of the following statements is true regarding fibrous connective tissue?

It is located between cortical and cancellous bone.

It is maintained and repaired by osteoblasts.

It is vascularized and innervated.

It has a matrix made up of fibers.

It provides support and stability to joints.

16 / 40

16. What structure quickens the propagation of action potentials on the muscle fiber?

Myofibrils

T-tubules

Sarcomeres

Acetylcholine

Troponin

17 / 40

17. What is the purpose of the sarcoplasmic reticulum in muscle fibers?

To allow ion exchange and electrical impulse propagation.

To contract and shorten the sarcomeres.

To hold the myofilaments in place within the sarcomeres.

To release stored calcium ions into the sarcoplasm.

To produce graded potentials on the muscle fibers.

18 / 40

18. Which of the following is NOT a component of the limbic system?

Thalamus

Medulla oblongata

Hippocampus

Hypothalamus

Amygdala

19 / 40

19. Which glial cell type produces cerebrospinal fluid?

Microglial cells

Ependymal cells

Schwann cells

Astrocytes

Oligodendrocytes

20 / 40

20. What is the function of memory B cells?

To present antigens to T cells

To produce and release antibodies

To recognize self proteins

To stimulate innate immunity

To directly kill infected cells

21 / 40

21. Which of the following is true about myoglobin?

It is a single peptide with one heme cofactor

It is found within erythrocytes

It undergoes cooperativity

It has a lower affinity for oxygen than oxyhemoglobin

It transports most of the oxygen traveling in the blood.

22 / 40

22. What is the minimum amount of air that needs to be present in the lungs to prevent collapse?

Functional residual capacity.

Inspiratory reserve volume

Expiratory reserve volume

Tidal volume

Residual volume

23 / 40

23. What is the role of oncotic pressure in the capillaries?

Pushes fluid out of the capillaries on the arterial end

Filters lymph through lymph nodes

Propels lymph via peristalsis

Brings fluid back into the capillaries at the venule end

Collects interstitial fluid, bacteria, fats, and proteins

24 / 40

24. Which of the following is true regarding invertebrate circulation?

Earthworms have an open circulatory system

Arthropods have a closed circulatory system

All of the above are false

Echinoderms use an open circulatory system

All invertebrates use a simple diffusion system to distribute nutrients

25 / 40

25. Which of the following is true about gymnosperms?

They have independent gametophyte and sporophyte life-cycles.

Their seeds are protected.

They are the most abundant type of plant.

Their sperm is dispersed in seeds by wind.

They have flagellated sperm.

26 / 40

26. Which characteristic is unique to the phylum Mollusca?

Segmentation

Metamorphosis

Radula

Cnidocytes

Tube feet

27 / 40

27. What is the primary feature that distinguishes the three domains of life: Archaea, Bacteria, and Eukarya?

Their cell structure

Their ability to reproduce

Their metabolic processes

Their ability to produce spores

Their size

28 / 40

28. What is the primary goal of fluorescence recovery after photobleaching (FRAP)?

To measure the fluorescence lifetime of a cell.

To measure the movement of biomolecules in a live cell.

To identify the function of a gene.

To increase the concentration of solute in a solution.

To identify the localization of proteins of interest.

29 / 40

29. What type of microscopy is capable of visualizing fluorescent objects and reduces artifacts by focusing a beam of UV light onto the sample?

Fluorescence microscopy

Optical microscopy

Electron microscopy

Confocal laser scanning microscopy

Phase contrast microscopy

30 / 40

30. What is a haplotype?

A group of genes that are inherited from one parent.

A group of genes that are inherited separately because they are located on different chromosomes.

A group of genes that are usually inherited together because they are located in close proximity to each other.

A group of genes that are inherited from both parents.

A group of genes that are not inherited.

31 / 40

31. What is the role of telomerase in DNA replication?

It replaces RNA primers with DNA.

It adds RNA primers at the origin of replication.

It binds to uncoiled DNA strands to prevent reattachment.

It unzips the DNA strands.

It extends telomeres to prevent DNA loss.

32 / 40

32. In prokaryotic transcription, how does a termination sequence end the transcription process in Rho independent termination?

It causes supercoiling in the DNA strand.

It binds to the promoter region, stopping transcription.

The RNA transcript folds into a hairpin loop, causing the RNA polymerase to fall off.

It adds a sigma factor to the RNA polymerase.

It binds to the RNA polymerase, causing it to fall off.

33 / 40

33. How many pairs of autosomes are present in the human body?

1 pair

46 pairs

23 pairs

22 pairs

2 pairs

34 / 40

34. What is the term for the division of the nucleus?

Cytokinesis

Ploidy

Karyokinesis

Dyads

Centromeres

35 / 40

35. What is the main difference between heterotrophs and autotrophs?

Heterotrophs use photosynthesis, while autotrophs use cellular respiration.

Heterotrophs can make their own food, while autotrophs get energy from the food they eat.

Autotrophs can make their own food, while heterotrophs must get energy from the food they eat.

There is no difference between heterotrophs and autotrophs.

Autotrophs use cellular respiration, while heterotrophs use photosynthesis.

36 / 40

36. Where does beta-oxidation of free fatty acids occur in eukaryotic cells?

Golgi apparatus

Endoplasmic reticulum

Mitochondrial matrix

Cytosol

Nucleus

37 / 40

37. Which of the following is not evidence supporting the endosymbiotic theory?

Mitochondria and chloroplasts have the same number of ribosomes.

Mitochondria and chloroplasts possess their own circular DNA.

Mitochondria and chloroplasts contain a double membrane.

Mitochondria and chloroplasts reproduce independently of the host cell.

Mitochondria and chloroplasts are similar in size.

38 / 40

38. Which organelle is responsible for synthesizing lipids, producing steroid hormones, and detoxifying cells?

Rough endoplasmic reticulum

Peroxisomes

Lysosomes

Mitochondria

Smooth endoplasmic reticulum

39 / 40

39. Which of the following statements correctly describes the role of cholesterol in the cell membrane?

It attaches cells to other cells.

It transmits signals all the way through the lipid bilayer.

It is used by cells to recognize other cells.

It makes the membrane less fluid at high temperatures and less fluid at low temperatures.

It binds to receptors and activates a target function.

40 / 40

40. Which type of bond is formed between two monosaccharides to form a disaccharide?

Intramolecular bond

Intermolecular bond

Covalent bond

Hydrogen bond

Ionic bond

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DAT Biology Practice Test #6

1 / 40

1. In the context of animal behaviors, what is the purpose of communication?

To foster non-associative learning

To increase an animal's fitness

To coordinate social behaviors with other animals

To facilitate classical conditioning

To trigger a Fixed Action Pattern

2 / 40

2. Which type of learning is NOT necessarily associated with reinforcement but involves an animal learning by observing another animal perform the same behavior?

Classical conditioning

Non-associative learning

Observational learning

Operant conditioning

Associative learning

3 / 40

3. What does the term 'brackish water' refer to in the context of aquatic biomes?

The water in the euphotic zone where sunlight penetrates all the way to the ocean floor

The water in the disphotic zone where there is semi-irradiation from the sun

The water where bioluminescent species produce light

The mixing of freshwater and saltwater, particularly in estuaries

The water in the aphotic zone where there is no light or photosynthetic species

4 / 40

4. What kind of organism is an autotroph?

An organism that eats both plants and animals.

An organism that produces organic compounds from abiotic factors.

An organism that must ingest organic compounds to generate energy.

An organism that utilizes inorganic compounds as their electron donors during cell respiration.

An organism that eats only plants.

5 / 40

5. How does biochemistry provide evidence of evolution?

By comparing the anatomy of different animals.

By studying the fossils of different species from various time periods.

By studying the spread of different species around the world.

By comparing DNA sequences and observing common conserved pathways in different species.

By observing embryological similarities and differences between related organisms.

6 / 40

6. During oogenesis, when does an ovum complete meiosis I?

At puberty, during each monthly cycle.

During the follicular phase of the menstrual cycle.

When it is fertilized.

During the embryonic development.

During the luteal phase of the menstrual cycle.

7 / 40

7. What is the purpose of positive feedback loops in hormonal regulation?

To inhibit a pathway and decrease production

To stimulate a pathway and increase production

To decrease hormone production when levels are too high

To facilitate the storage of hormones for future use

To maintain the body's homeostasis

8 / 40

8. What differentiates the papillary dermis from the reticular dermis?

The papillary dermis is more superficial and thin, while the reticular dermis is deeper and thick

The papillary dermis is made of squamous cells, while the reticular dermis is made of columnar cells

The papillary dermis contains sebaceous glands, while the reticular dermis contains sweat glands

The papillary dermis contains hair follicles, while the reticular dermis does not

The papillary dermis is deeper than the reticular dermis

9 / 40

9. What is the function of the keratinocytes in the epidermis?

They store fat for insulation

They produce melanin for skin color

They produce vitamin D in response to sunlight

They secrete sweat for thermoregulation

They protect against dehydration, UV radiation, and pathogens

10 / 40

10. Which hormone is inhibited by the intake of alcohol, leading to increased urination?

Renin

Aldosterone

Antidiuretic Hormone (ADH)

Atrial natriuretic peptide (ANP)

Angiotensin II

11 / 40

11. What is the primary function of the villi and microvilli in the small intestine?

They secrete mucus to lubricate the intestinal walls.

They protect the lining of the intestine from acidic chyme.

They produce digestive enzymes.

They facilitate peristalsis, aiding in the movement of food through the intestine.

They increase the surface area of the intestine, enhancing nutrient absorption.

12 / 40

12. Where does most digestion and nutrient absorption occur within the human body?

The large intestine

The stomach

The small intestine

The mouth and esophagus

The liver and gallbladder

13 / 40

13. Which gland produces melatonin, and what is its main function?

The pineal gland produces melatonin to regulate circadian rhythm.

The thyroid gland produces melatonin to increase metabolism.

The hypothalamus produces melatonin to maintain homeostasis.

The pituitary gland produces melatonin to stimulate body cells to grow and divide.

The adrenal gland produces melatonin to fight stress.

14 / 40

14. Which hormone stimulates the release of glucocorticoids from the adrenal gland?

Prolactin

Luteinizing hormone (LH)

Follicle stimulating hormone (FSH)

Adrenocorticotropic hormone (ACTH)

Thyroid stimulating hormone (TSH)

15 / 40

15. Which type of joint partially moves and is cartilaginous?

Fibrous joints

Amphiarthroses

Diarthroses

Synarthroses

Hyaline joints

16 / 40

16. Which of the following statements accurately describes the H zone?

The H zone is the area in the sarcomere where only thick myosin filaments are present.

The H zone is the area in the sarcomere where only myosin filaments are present.

The H zone is the midpoint of the sarcomere.

The H zone is the area in the sarcomere where actin and myosin overlap.

The H zone is the area in the sarcomere where only thin actin filaments are present.

17 / 40

17. What is rigor mortis?

A condition in which the sarcoplasmic reticulum is damaged.

A state of muscle relaxation.

A state of muscle contraction that occurs in living animals.

The state of muscle contraction that occurs after death due to the absence of ATP.

The state of muscle contraction that occurs when there is an excess of ATP.

18 / 40

18. What is the function of microglial cells?

To form the myelin sheath

To protect the central nervous system

To form the blood-brain barrier

To produce cerebrospinal fluid

To help support and surround neurons

19 / 40

19. Which of the following is not a part of the neuron?

Soma

Dendrites

Synapse

Axon

All of the above are parts of the neuron

20 / 40

20. Which type of immunity is gained from receiving antibodies from another organism that already has that immunity?

Passive immunity

Active immunity

Humoral immunity

Artificial immunity

Innate immunity

21 / 40

21. How does decreased pH affect hemoglobin's affinity for oxygen?

Decreased pH increases hemoglobin's affinity for oxygen

Decreased pH reduces hemoglobin's affinity for oxygen

Decreased pH has no effect on hemoglobin's affinity for oxygen

None of the above

Decreased pH eliminates hemoglobin's affinity for oxygen

22 / 40

22. Which of the following conditions is caused by rapid breathing?

None of the above

Metabolic acidosis

Respiratory acidosis

Respiratory alkalosis

Metabolic alkalosis

23 / 40

23. Which of the following statements is true about the chordates' circulatory system?

Homeothermic chordates have a 3-chambered heart

Fish have a 4-chambered heart

Most chordates have an open circulatory system

Reptiles and amphibians have 4-chambered hearts

The alligators and crocodiles are an exception and have a 3-chambered heart

24 / 40

24. Which of the following statements is true about heart sounds?

The “dub” sound is caused by atria contracting while the ventricles are relaxing

The “lub” sound is caused by semilunar valves snapping shut

The semilunar valves snap shut during the dub sound

Diastole occurs between the lub and dub sounds

Systole occurs between the dub and next lub sound

25 / 40

25. Which of the following is not a component of the pistil?

Filament

Ovary

Stigma

Style

All of the above are components of the pistil.

26 / 40

26. Which of the following is a characteristic of fungi?

Unicellular and multicellular forms

Presence of cell wall made of chitin

All of the above

Eukaryotic and prokaryotic forms

Photosynthetic ability

27 / 40

27. Which phylum is characterized by having a gastrovascular cavity for digestion?

Annelida

Mollusca

Cnidaria

Nematoda

Platyhelminthes

28 / 40

28. What is the difference between totipotent, pluripotent, and multipotent cells?

Their ability to differentiate into different types of cells.

Their ability to carry genetic information.

Their ability to be found in different parts of the body.

Their ability to replicate.

Their size and shape.

29 / 40

29. Which of the following cellular biological lab techniques is based on the principle of electrical resistance?

Automated cell counting

Hemocytometers

Differential centrifugation

Colony Forming Units (CFUs)

Bacterial growth curve

30 / 40

30. What is a Pedigree chart used for?

To track inherited traits over many generations to see inheritance patterns.

To visualize the process of nondisjunction during cell division.

To determine the genotype of an individual in a cross.

To visualize the process of crossing over during prophase I of meiosis.

To illustrate the process of gene linkage.

31 / 40

31. Which of the following best describes the role of the TATA box in eukaryotic transcription?

It is an enzyme that adds adenine nucleotides to the 3’ end of the mRNA.

It is an enzyme that attaches an amino acid to a specific tRNA using ATP.

It is a DNA site where repressor proteins bind to decrease gene transcription.

It is a protein that assists newly synthesized polypeptides to fold into their correct shape.

It is a sequence in many promoters that transcription factors recognize and bind to.

32 / 40

32. What is the function of topoisomerase in the process of DNA replication?

It nicks the DNA double helix ahead of helicase to relieve built-up tension and supercoiling.

It places RNA primers at the origin of replication to create 3’ ends for nucleotide addition.

It holds DNA polymerase onto the template strand.

It adds free nucleoside triphosphates to 3’ ends.

It unzips the DNA by breaking hydrogen bonds between strands.

33 / 40

33. What is the purpose of anchorage dependence in cell regulation?

To signal for cell division

To check for chromosomal attachment to spindle fibers

To halt cell division when density of cells is high

To divide only when attached to an external surface

To prevent cancerous growth

34 / 40

34. What happens during the S phase of the cell cycle?

The physical separation of the cytoplasm and cell membrane into two daughter cells occurs

Cell grows in preparation for division

Cell checks DNA for any errors after replication

Cell replicates its genome

Cells carry out their functions but halt in the cell cycle

35 / 40

35. What is the final product of the Calvin cycle?

Oxygen

ATP and NADPH

Water

Carbon dioxide

Glucose

36 / 40

36. Why are proteins considered the least desirable source of energy?

All of the above

They are difficult to break down

They require a considerable amount of energy to enter cellular respiration

They are needed for essential functions in the body

None of the above

37 / 40

37. What happens to pyruvate in pyruvate oxidation?

It is converted into glucose.

It is converted into ATP.

It is converted into NADH.

It is converted into ADP.

It is converted into acetyl-CoA.

38 / 40

38. Which of the following statements correctly describes the function of microfilaments in the cytoskeleton?

They assist in cell movement and can quickly assemble and disassemble.

They are involved in the formation of the nuclear lamina.

They act as motor proteins that transport cargo along microtubules.

They mainly provide structural support, like keratin in skin, hair, and nails.

They are hollow structures that have walls made of tubulin protein dimers.

39 / 40

39. What is the main difference between integral and peripheral membrane proteins?

Integral proteins increase the fluidity of the cell membrane, while peripheral proteins decrease it.

Integral proteins introduce kinks in the lipid bilayer, while peripheral proteins do not.

Integral proteins are composed of glycoproteins, while peripheral proteins are not.

Integral proteins are amphipathic, while peripheral proteins are hydrophilic.

Integral proteins bind to receptors, while peripheral proteins do not.

40 / 40

40. What is a proteome?

The set of amino acids in a polypeptide

The sequence of amino acids connected through peptide bonds

The three-dimensional structure of a protein

All of the proteins expressed by one type of cell under one set of conditions

None of the above

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