BIOS 256 Exam 3 Questions and Answers with Rationales |
CHAMBERLAIN UNIVERSITY
Question 1. Which function is the best match for fetal circulation shunts?
A. maintains the corpus luteum in early pregnancy until placental steroid production is established
B. direct blood around organs that are not yet performing adult gas-exchange or hepatic functions
C. supports exchange of gases, nutrients, and wastes and produces hormones that help maintain pregnancy
D. includes intense organogenesis and therefore high vulnerability to major structural defects
Correct Answer: B. direct blood around organs that are not yet performing adult gas-exchange or hepatic
functions
Explanation: The correct choice describes this function: direct blood around organs that are not yet performing adult
gas-exchange or hepatic functions. This is the primary role associated with fetal circulation shunts, and it is supported by
the mechanism that placental oxygenation and pressure relationships route blood through these shunts before birth. The
other choices describe functions performed by different components within the same course domain.
Question 2. Consider this case: A man has normal sperm production but markedly reduced seminal fluid
from loss of the paired glands behind the bladder. What is the best physiologic explanation?
A. the procedure interrupts the ductus deferens
B. the duct is the epididymis
C. the seminal vesicles normally contribute a large fraction of semen volume
D. the prostate can compress the urethra when enlarged
Correct Answer: C. the seminal vesicles normally contribute a large fraction of semen volume
Explanation: The best interpretation is that the seminal vesicles normally contribute a large fraction of semen volume.
This scenario centers on seminal vesicles, whose normal physiologic role is described as follows: contribute most of the
fluid volume of semen and provide nutrients and signaling molecules. That relationship is more directly supported by the
stated findings than the alternative explanations.
Question 3. What physiologic function is most directly associated with germ layers?
A. give rise to all major tissues and organs of the developing body
B. combines haploid gametes to form a diploid zygote and initiates embryonic development
C. increase cell number without a large increase in overall conceptus size during early transit toward the uterus
D. establish the early embryonic relationship with the uterine endometrium
Correct Answer: A. give rise to all major tissues and organs of the developing body
Explanation: The correct choice describes this function: give rise to all major tissues and organs of the developing body.
This is the primary role associated with germ layers, and it is supported by the mechanism that cell migration and
differentiation create three foundational tissue layers with characteristic developmental fates. The other choices describe
functions performed by different components within the same course domain.
,Question 4. Which normal outcome is most directly associated with intact renal acid-base regulation
physiology?
A. The system demonstrates that it rapidly catalyzes interconversion of carbon dioxide and water with carbonic
acid.
B. The system demonstrates that it reduce but do not reverse the direction of the primary disorder.
C. The system demonstrates that it changes alveolar ventilation to partially offset a primary metabolic acid-base
disorder.
D. The system demonstrates that it provides slower but powerful control by reabsorbing filtered bicarbonate and
excreting net acid.
Correct Answer: D. The system demonstrates that it provides slower but powerful control by reabsorbing
filtered bicarbonate and excreting net acid.
Explanation: The strongest evidence is the outcome linked to the normal role of renal acid-base regulation: provides
slower but powerful control by reabsorbing filtered bicarbonate and excreting net acid. This expected result depends on
the mechanism that ammonium and phosphate buffering permit hydrogen excretion without lowering urine pH
indefinitely. The other outcomes would point to different physiologic functions rather than intact renal acid-base
regulation activity.
Question 5. Severe dysfunction involving uterus would be expected to cause which outcome first?
A. menstruation follows the loss of ovarian steroid support when pregnancy does not occur
B. fertility can fall and ectopic implantation risk can rise when tubal transport is impaired
C. ovulation and normal cyclic estrogen production would be impaired if follicles failed to mature
D. implantation and pregnancy maintenance would fail if the uterine lining could not respond to hormones
Correct Answer: D. implantation and pregnancy maintenance would fail if the uterine lining could not respond
to hormones
Explanation: The most direct consequence is that implantation and pregnancy maintenance would fail if the uterine
lining could not respond to hormones. That prediction follows because uterus normally has this role: supports
implantation, placental development, fetal growth, and parturition. The distractors reflect dysfunction of other structures
or processes rather than the most direct consequence here.
Question 6. Which combination correctly matches osmolarity with an identifying feature and a likely
consequence of severe dysfunction?
A. Feature: most potassium is inside cells, and small extracellular changes strongly affect cardiac and
neuromuscular function / Dysfunction: neuronal function can be disturbed when rapid osmotic shifts cause cell
swelling or shrinkage.
B. Feature: most body sodium is outside cells and its total content is regulated primarily by renal excretion and
reabsorption / Dysfunction: neuronal function can be disturbed when rapid osmotic shifts cause cell swelling or
shrinkage.
C. Feature: small changes in extracellular osmolarity can shift water across cell membranes / Dysfunction: neuronal
function can be disturbed when rapid osmotic shifts cause cell swelling or shrinkage.
D. Feature: intracellular fluid contains the larger share of total body water, while extracellular fluid includes
interstitial fluid and plasma / Dysfunction: neuronal function can be disturbed when rapid osmotic shifts cause cell
swelling or shrinkage.
Correct Answer: C. Feature: small changes in extracellular osmolarity can shift water across cell membranes /
Dysfunction: neuronal function can be disturbed when rapid osmotic shifts cause cell swelling or shrinkage.
Explanation: For osmolarity, the identifying feature is that small changes in extracellular osmolarity can shift water
across cell membranes, and severe dysfunction would mean that neuronal function can be disturbed when rapid osmotic
shifts cause cell swelling or shrinkage. Both halves of the pairing must be correct for the option to be valid. The
distractors combine the correct consequence with a defining feature that belongs to another item.
, Question 7. The finding 'it contains fetal chorionic tissue closely associated with maternal uterine tissue
while the two blood supplies normally remain separate' most specifically points to which item?
A. placenta
B. embryonic period and teratogen sensitivity
C. fetal circulation shunts
D. human chorionic gonadotropin
Correct Answer: A. placenta
Explanation: The description identifies placenta because it contains fetal chorionic tissue closely associated with
maternal uterine tissue while the two blood supplies normally remain separate. Its key role is that it supports exchange of
gases, nutrients, and wastes and produces hormones that help maintain pregnancy. The alternative options have different
defining features and do not best fit the description.
Question 8. A student creates a two-column study card for sodium balance. Which feature/effect pair is
correct?
A. Feature: intracellular fluid contains the larger share of total body water, while extracellular fluid includes
interstitial fluid and plasma / Dysfunction: extracellular volume can contract or expand when total-body sodium
balance changes.
B. Feature: most body sodium is outside cells and its total content is regulated primarily by renal excretion and
reabsorption / Dysfunction: extracellular volume can contract or expand when total-body sodium balance changes.
C. Feature: most potassium is inside cells, and small extracellular changes strongly affect cardiac and
neuromuscular function / Dysfunction: extracellular volume can contract or expand when total-body sodium
balance changes.
D. Feature: small changes in extracellular osmolarity can shift water across cell membranes / Dysfunction:
extracellular volume can contract or expand when total-body sodium balance changes.
Correct Answer: B. Feature: most body sodium is outside cells and its total content is regulated primarily by
renal excretion and reabsorption / Dysfunction: extracellular volume can contract or expand when total-body
sodium balance changes.
Explanation: For sodium balance, the identifying feature is that most body sodium is outside cells and its total content is
regulated primarily by renal excretion and reabsorption, and severe dysfunction would mean that extracellular volume
can contract or expand when total-body sodium balance changes. Both halves of the pairing must be correct for the
option to be valid. The distractors combine the correct consequence with a defining feature that belongs to another item.
Question 9. Which function is the best match for polygenic and multifactorial traits?
A. produces haploid gametes so fertilization can restore the diploid chromosome number
B. can produce a trait when one altered allele on an autosome is sufficient for expression
C. arise from combined effects of multiple genes and often environmental influences
D. often affects males more frequently because they have only one X chromosome
Correct Answer: C. arise from combined effects of multiple genes and often environmental influences
Explanation: The correct choice describes this function: arise from combined effects of multiple genes and often
environmental influences. This is the primary role associated with polygenic and multifactorial traits, and it is supported
by the mechanism that many alleles contribute small effects that interact with nutrition, exposures, or other
environmental factors. The other choices describe functions performed by different components within the same course
domain.
CHAMBERLAIN UNIVERSITY
Question 1. Which function is the best match for fetal circulation shunts?
A. maintains the corpus luteum in early pregnancy until placental steroid production is established
B. direct blood around organs that are not yet performing adult gas-exchange or hepatic functions
C. supports exchange of gases, nutrients, and wastes and produces hormones that help maintain pregnancy
D. includes intense organogenesis and therefore high vulnerability to major structural defects
Correct Answer: B. direct blood around organs that are not yet performing adult gas-exchange or hepatic
functions
Explanation: The correct choice describes this function: direct blood around organs that are not yet performing adult
gas-exchange or hepatic functions. This is the primary role associated with fetal circulation shunts, and it is supported by
the mechanism that placental oxygenation and pressure relationships route blood through these shunts before birth. The
other choices describe functions performed by different components within the same course domain.
Question 2. Consider this case: A man has normal sperm production but markedly reduced seminal fluid
from loss of the paired glands behind the bladder. What is the best physiologic explanation?
A. the procedure interrupts the ductus deferens
B. the duct is the epididymis
C. the seminal vesicles normally contribute a large fraction of semen volume
D. the prostate can compress the urethra when enlarged
Correct Answer: C. the seminal vesicles normally contribute a large fraction of semen volume
Explanation: The best interpretation is that the seminal vesicles normally contribute a large fraction of semen volume.
This scenario centers on seminal vesicles, whose normal physiologic role is described as follows: contribute most of the
fluid volume of semen and provide nutrients and signaling molecules. That relationship is more directly supported by the
stated findings than the alternative explanations.
Question 3. What physiologic function is most directly associated with germ layers?
A. give rise to all major tissues and organs of the developing body
B. combines haploid gametes to form a diploid zygote and initiates embryonic development
C. increase cell number without a large increase in overall conceptus size during early transit toward the uterus
D. establish the early embryonic relationship with the uterine endometrium
Correct Answer: A. give rise to all major tissues and organs of the developing body
Explanation: The correct choice describes this function: give rise to all major tissues and organs of the developing body.
This is the primary role associated with germ layers, and it is supported by the mechanism that cell migration and
differentiation create three foundational tissue layers with characteristic developmental fates. The other choices describe
functions performed by different components within the same course domain.
,Question 4. Which normal outcome is most directly associated with intact renal acid-base regulation
physiology?
A. The system demonstrates that it rapidly catalyzes interconversion of carbon dioxide and water with carbonic
acid.
B. The system demonstrates that it reduce but do not reverse the direction of the primary disorder.
C. The system demonstrates that it changes alveolar ventilation to partially offset a primary metabolic acid-base
disorder.
D. The system demonstrates that it provides slower but powerful control by reabsorbing filtered bicarbonate and
excreting net acid.
Correct Answer: D. The system demonstrates that it provides slower but powerful control by reabsorbing
filtered bicarbonate and excreting net acid.
Explanation: The strongest evidence is the outcome linked to the normal role of renal acid-base regulation: provides
slower but powerful control by reabsorbing filtered bicarbonate and excreting net acid. This expected result depends on
the mechanism that ammonium and phosphate buffering permit hydrogen excretion without lowering urine pH
indefinitely. The other outcomes would point to different physiologic functions rather than intact renal acid-base
regulation activity.
Question 5. Severe dysfunction involving uterus would be expected to cause which outcome first?
A. menstruation follows the loss of ovarian steroid support when pregnancy does not occur
B. fertility can fall and ectopic implantation risk can rise when tubal transport is impaired
C. ovulation and normal cyclic estrogen production would be impaired if follicles failed to mature
D. implantation and pregnancy maintenance would fail if the uterine lining could not respond to hormones
Correct Answer: D. implantation and pregnancy maintenance would fail if the uterine lining could not respond
to hormones
Explanation: The most direct consequence is that implantation and pregnancy maintenance would fail if the uterine
lining could not respond to hormones. That prediction follows because uterus normally has this role: supports
implantation, placental development, fetal growth, and parturition. The distractors reflect dysfunction of other structures
or processes rather than the most direct consequence here.
Question 6. Which combination correctly matches osmolarity with an identifying feature and a likely
consequence of severe dysfunction?
A. Feature: most potassium is inside cells, and small extracellular changes strongly affect cardiac and
neuromuscular function / Dysfunction: neuronal function can be disturbed when rapid osmotic shifts cause cell
swelling or shrinkage.
B. Feature: most body sodium is outside cells and its total content is regulated primarily by renal excretion and
reabsorption / Dysfunction: neuronal function can be disturbed when rapid osmotic shifts cause cell swelling or
shrinkage.
C. Feature: small changes in extracellular osmolarity can shift water across cell membranes / Dysfunction: neuronal
function can be disturbed when rapid osmotic shifts cause cell swelling or shrinkage.
D. Feature: intracellular fluid contains the larger share of total body water, while extracellular fluid includes
interstitial fluid and plasma / Dysfunction: neuronal function can be disturbed when rapid osmotic shifts cause cell
swelling or shrinkage.
Correct Answer: C. Feature: small changes in extracellular osmolarity can shift water across cell membranes /
Dysfunction: neuronal function can be disturbed when rapid osmotic shifts cause cell swelling or shrinkage.
Explanation: For osmolarity, the identifying feature is that small changes in extracellular osmolarity can shift water
across cell membranes, and severe dysfunction would mean that neuronal function can be disturbed when rapid osmotic
shifts cause cell swelling or shrinkage. Both halves of the pairing must be correct for the option to be valid. The
distractors combine the correct consequence with a defining feature that belongs to another item.
, Question 7. The finding 'it contains fetal chorionic tissue closely associated with maternal uterine tissue
while the two blood supplies normally remain separate' most specifically points to which item?
A. placenta
B. embryonic period and teratogen sensitivity
C. fetal circulation shunts
D. human chorionic gonadotropin
Correct Answer: A. placenta
Explanation: The description identifies placenta because it contains fetal chorionic tissue closely associated with
maternal uterine tissue while the two blood supplies normally remain separate. Its key role is that it supports exchange of
gases, nutrients, and wastes and produces hormones that help maintain pregnancy. The alternative options have different
defining features and do not best fit the description.
Question 8. A student creates a two-column study card for sodium balance. Which feature/effect pair is
correct?
A. Feature: intracellular fluid contains the larger share of total body water, while extracellular fluid includes
interstitial fluid and plasma / Dysfunction: extracellular volume can contract or expand when total-body sodium
balance changes.
B. Feature: most body sodium is outside cells and its total content is regulated primarily by renal excretion and
reabsorption / Dysfunction: extracellular volume can contract or expand when total-body sodium balance changes.
C. Feature: most potassium is inside cells, and small extracellular changes strongly affect cardiac and
neuromuscular function / Dysfunction: extracellular volume can contract or expand when total-body sodium
balance changes.
D. Feature: small changes in extracellular osmolarity can shift water across cell membranes / Dysfunction:
extracellular volume can contract or expand when total-body sodium balance changes.
Correct Answer: B. Feature: most body sodium is outside cells and its total content is regulated primarily by
renal excretion and reabsorption / Dysfunction: extracellular volume can contract or expand when total-body
sodium balance changes.
Explanation: For sodium balance, the identifying feature is that most body sodium is outside cells and its total content is
regulated primarily by renal excretion and reabsorption, and severe dysfunction would mean that extracellular volume
can contract or expand when total-body sodium balance changes. Both halves of the pairing must be correct for the
option to be valid. The distractors combine the correct consequence with a defining feature that belongs to another item.
Question 9. Which function is the best match for polygenic and multifactorial traits?
A. produces haploid gametes so fertilization can restore the diploid chromosome number
B. can produce a trait when one altered allele on an autosome is sufficient for expression
C. arise from combined effects of multiple genes and often environmental influences
D. often affects males more frequently because they have only one X chromosome
Correct Answer: C. arise from combined effects of multiple genes and often environmental influences
Explanation: The correct choice describes this function: arise from combined effects of multiple genes and often
environmental influences. This is the primary role associated with polygenic and multifactorial traits, and it is supported
by the mechanism that many alleles contribute small effects that interact with nutrition, exposures, or other
environmental factors. The other choices describe functions performed by different components within the same course
domain.
