Recitation Practice Questions, Unit 3

Question 1

At puberty, an adolescent female body changes in both structure and function of several organ systems, primarily under the influence of changing concentrations of estrogens and other steroid hormones. How can one hormone, such as estrogen, mediate so many effects?
A.Estrogen is produced in very large concentrations and therefore diffuses widely.
B.Estrogen has specific receptors inside several cell types, but each cell responds in the same way to its binding.
C.Estrogen is kept away from the surface of any cells not able to bind it at the surface.
D.Estrogen binds to specific receptors inside many kinds of cells, each of which have different responses to its binding.
E.Estrogen has different shaped receptors for each of several cell types

Answer 1

D.Estrogen binds to specific receptors inside many kinds of cells, each of which have different responses to its binding.

Question 2

In humans, the follicular cells that remain behind in the ovary following ovulation become ________.
A. the ovarian endometrium that is shed at the time of the menses.
B. a steroid-hormone synthesizing structure called the corpus luteum.
C. the thickened portion of the uterine wall.
D. swept into the fallopian tube.
E. the placenta, which secretes cervical mucus.

Answer 2

B. a steroid-hormone synthesizing structure called the corpus luteum.

Question 3

Sexual reproduction _______.
A. Allows animals to conserve resources and reproduce only during optimal conditions.
B. Can produce diverse phenotypes that may enhance survival of a population in a changing environment.
C. Yields more numerous offspring more rapidly than is possible with asexual reproduction.
D. Enables males and females to remain isolated from each other while rapidly colonizing habitats.
E. Guarantees that both parents will provide care for each offspring.

Answer 3

B. Can produce diverse phenotypes that may enhance survival of a population in a changing environment.

Question 4

Animals with reproduction dependent on internal fertilization need not have ________.
A. Any copulatory organs.
B. A receptacle that receives sperm.
C. Behavioral interaction between males and females.
D. Internal development of embryos.
E. Haploid gametes.

Answer 4

D. Internal development of embryos.

Question 5

For lactation to take place, ________ stimulates the synthesis of breast milk and ________ causes milk expulsion.
A. Testosterone; dihydrotestosterone.
B. Estrogen; progesterone.
C. Cortisol; testosterone.
D. Prolactin; oxytocin.
E. Luteinizing hormone; follicle stimulating hormone

Answer 5

D. Prolactin; oxytocin.

Question 6

Which of the following is NOT true about the production of gametes?
A. The term spermatogenesis refers to the overall process of the production of sperm cells.
B. Human males are born with a finite amount of sperm cells and do not produce any more sperm cells throughout the rest of their lifetime.
C. Hormones play a role in the regulation of the production of gametes.
D. Gametes only carry half the genetic material somatic cells do.
E. None of the above.

Answer 6

B. Human males are born with a finite amount of sperm cells and do not produce any more sperm cells throughout the rest of their lifetime.

Question 7

At the time of fertilization, the complete maturation of each oogonium has resulted in ________.
A. One secondary oocyte.
B. Two primary oocytes.
C. Four secondary oocytes.
D. Four primary oocytes.
E. Four zygotes.

Answer 7

A. One secondary oocyte

Question 8

Contact of a sperm with signal molecules in the coat of an egg causes the sperm to undergo ________.
A. Mitosis.
B. Depolarization.
C. Apoptosis.
D. Vitellogenesis.
E. The acrosomal reaction

Answer 8

E. The acrosomal reaction

Question 9

A contraceptive pill that continuously inhibits the release of GnRH from the hypothalamus will ________.
A. Increase the production of estrogen and progesterone by the ovaries.
B. Initiate ovulation.
C. Reduce the secretion of gonadotropins from the anterior pituitary gland.
D. Stimulate the secretion of LH and FSH from the posterior pituitary gland.
E. Increase the flow phase of the menstrual cycle

Answer 9

C. Reduce the secretion of gonadotropins from the anterior pituitary gland.

Question 10

An inhibitor of phosphodiesterase activity would have which of the following effects?
A. Block the response of epinephrine.
B. Decrease the amount of cAMP in the cytoplasm.
C. Block the activation of G proteins in response to epinephrine binding to its receptor.
D. Prolong the effect of epinephrine by maintaining elevated cAMP levels in the cytoplasm.
E. Block the activation of protein kinase A

Answer 10

D. Prolong the effect of epinephrine by maintaining elevated cAMP levels in the cytoplasm.

Question 11

Which of the following is a FALSE statement regarding action potentials?
A. The membrane potential becomes more negative just before getting back to its resting state.
B. It is possible for summation of action potentials to occur.
C. Action potentials are set off by a change in the membrane potential.
D. Voltage-gated ion channels do not play a significant role in the initiation of action potentials.
E. None of the above

Answer 11

Voltage-gated ion channels do not play a significant role in the initiation of action potentials.

Question 12

Neurotransmitters are released from axon terminals via ________.
A. Osmosis
B. Active transport
C. Diffusion
D. Transcytosis
E. Exocytosis

Answer 12

Exocytosis

Question 13

Neurotransmitters categorized as inhibitory would be expected to …
A. Act independently of their receptor proteins.
B. Close potassium channels.
C. Open sodium channels.
D. Close chloride channels.
E. Hyperpolarize the membrane

Answer 13

Hyperpolarize the membrane

Question 14

A toxin that binds specifically to voltage-gated sodium ion (Na+) channels in axons would be expected to …
A. Prevent the hyperpolarization phase of the action potential.
B. Prevent the depolarization phase of the action potential.
C. Prevent graded potentials.
D. Increase the release of neurotransmitter molecules.
E. Have most of its effects on the dendritic region of a neuron.

Answer 14

Prevent the depolarization phase of the action potential.

Question 15

Excessive consumption of ethanol increases the influx of negative chloride ions into ʺcommon senseʺ neurons whose action potentials are needed for you to act appropriately and not harm yourself or others. So, any resulting poor decisions associated with ethanol ingestion are most likely due to _______.
A. Increased membrane depolarization of ʺcommon senseʺ neurons.
B. Decreased membrane depolarization of ʺcommon senseʺ neurons.
C. More action potentials in your ʺcommon senseʺ neurons.
D. More EPSPs in your ʺcommon senseʺ neurons.
E. Fewer IPSPs in your ʺcommon senseʺ neurons.

Answer 15

B. Decreased membrane depolarization of ʺcommon senseʺ neurons.

Question 16

Which of the following is the best explanation for the inability of an animal cell to reduce the Ca2+ (calcium ion) concentration in its cytosol compared with the extracellular fluid?
A. Blockage of the synaptic signal.
B. Loss of transcription factors.
C. Insufficient ATP levels in the cytoplasm.
D. Low oxygen concentration around the cell.
E. Low levels of protein kinase in the cell

Answer 16

C. Insufficient ATP levels in the cytoplasm.

Question 17

The filtrate in the renal pelvis enters directly from __.
A. the loop of Henle.
B. the collecting duct.
C. Bowman’s capsule.
D. the proximal tubule.
E. the glomerulus.

Answer 17

B. the collecting duct.

Question 18

The body fluids of an osmoconformer would be __________ with its __________ environment.
A. Hyperosmotic; freshwater.
B. Isotonic; freshwater.
C. Hyperosmotic; saltwater.
D. Iso-osmotic; saltwater.
E. Hypoosmotic; saltwater

Answer 18

D. Iso-osmotic; saltwater.

Question 19

A marine sea star was mistakenly placed in freshwater and it died. What is the most likely explanation for its death?
A. The sea star was stressed and needed more time to acclimate to new conditions.
B. The sea star is hyperosmotic to the freshwater, and it could not osmoregulate.
C. The osmoregulatory system of the sea star could not handle the change in ionic content presented by the freshwater.
D. The contractile vacuoles used to regulate water content ruptured in the freshwater.
E. The cells of the sea star dehydrated and lost the ability to metabolize

Answer 19

The sea star is hyperosmotic to the freshwater, and it could not osmoregulate.

Question 20

In animals, nitrogenous wastes are produced mostly from the catabolism of ________.
A. Starch and cellulose.
B. Triglycerides and steroids.
C. Proteins and nucleic acids.
D. Phospholipids and glycolipids.
E. Fatty acids and glycerol.

Answer 20

C. Proteins and nucleic acids.

Question 21

The transfer of fluid from the glomerulus to Bowmanʹs capsule ________.
A. Results from active transport.
B. Transfers large molecules as easily as small ones.
C. Is very selective as to which small sized molecules are transferred.
D. Usually includes the transfer of red blood cells to the Bowmanʹs capsule.
E. Is mainly a consequence of blood pressure in the capillaries of the glomerulus.

Answer 21

E. Is mainly a consequence of blood pressure in the capillaries of the glomerulus.

Question 22

Which one of the following, if present in a urine sample, would likely be caused by trauma?
Amino acids.
Glucose.
Salts.
Erythrocytes.
Vitamins.

Answer 22

Erythrocytes.

Question 23

How do ADH and RAAS work together in maintaining osmoregulatory homeostasis?
A. ADH monitors osmolarity of the blood and RAAS stimulates the sympathetic nervous system.
B. ADH monitors appropriate osmolarity by reabsorption of water, and RAAS maintains osmolarity by stimulating Na+ reabsorption.
C. ADH and RAAS work antagonistically; ADH stimulates water reabsorption during dehydration and RAAS removal of water when it is in excess in body fluids.
D. Both stimulate the adrenal gland to secrete aldosterone which increases both blood volume and pressure.
E. Only when they are together in the receptor sites of proximal tubule cells, will reabsorption of essential nutrients back into the blood take place.

Answer 23

ADH monitors appropriate osmolarity by reabsorption of water, and RAAS maintains osmolarity by stimulating Na+ reabsorption.

Question 24

Which of the following is the correct sequence of blood flow in reptiles and mammals?
A. left ventricle → aorta → lungs → systemic circulation
B. right ventricle → pulmonary vein → pulmocutaneous circulation
C. pulmonary vein → left atrium → left ventricle → pulmonary circuit
D. vena cava → right atrium → right ventricle → pulmonary circuit
E. right atrium → pulmonary artery → left atrium → ventricle

Answer 24

D. vena cava → right atrium → right ventricle → pulmonary circuit

Question 25

An anthropologist discovers fossilized animal remains that give strong evidence that the organism had a large, well-formed, most likely 4-chambered heart, with no connection between the right and left sides. Which of the following could most reasonably be hypothesized from this observation?
A. That the animal and its relatives had evolved from birds.
B. That the animal had a high energy requirement and was an endotherm.
C. That the animal was most closely related to reptiles such as alligators and crocodiles.
D. That the animal was a kind of invertebrate.
E. That the species had little to no need to regulate blood pressure.

Answer 25

That the animal had a high energy requirement and was an endotherm.

Question 26

Which of the following statements about our blood vessels is false?
A. Vasoconstriction of the blood vessels leads to a decrease in blood flow.
B. Vasodilation of the blood vessels leads to a decrease in blood pressure.
C. Smooth and skeletal muscle contractions which reduce the diameter of the lumen of a blood vessel will increase the blood pressure and velocity of blood flow in that blood vessel.
D. Veins have the lowest blood pressure and thus the lowest velocity of blood flow in comparison to arteries and capillaries.
E. None of the above

Answer 26

Veins have the lowest blood pressure and thus the lowest velocity of blood flow in comparison to arteries and capillaries.

Question 27

Consider an organism which has a circulating body fluid that is distinct from the fluid that directly surrounds the bodyʹs cells. Based off of this information, which of the following would you expect this animal to possess?
A. An open circulatory system.
B. A closed circulatory system.
C. A gastrovascular cavity.
D. Branched tracheae.
E. More than one of the above

Answer 27

B. A closed circulatory system.

Question 28

Which of the following would you NOT expect to observe when the heart is in the ventricular systole phase of the cardiac cycle?
A. Opening of the bicupsid and tricupsid valves.
B. Blood pouring into the left and right atria.
C. Blood pumped into the aorta and pulmonary arteries.
D. Blood being pumped out of the left ventricle while the right ventricle is filling with blood for the next phase of the cycle.
E. More than one of the above.

Answer 28

A. Opening of the bicupsid and tricupsid valves.
D. Blood being pumped out of the left ventricle while the right ventricle is filling with blood for the next phase of the cycle.
E. More than one of the above.

Question 29

Damage to the sinoatrial node in humans _______.
a. Is a major contributor to heart attacks.
b. Would directly block conductance between the bundle branches and the Purkinje fibers.
c. Would not affect the heart rate as there are also cardiac cells that are autorhythmic.
d. Would disrupt the rate and timing of cardiac muscle contractions.
e. More than one of the above.

Answer 29

Would disrupt the rate and timing of cardiac muscle contractions.