ATI Anatomy & Physiology Proctored Exam-style
practice test. Test 4 Question and Answers with
Rationales Top rated Latest Version
Question 1
A nurse is assessing a client with severe dehydration after several days
of vomiting. Which physiological response is expected to help maintain
blood pressure?
A. Decreased aldosterone secretion
B. Increased antidiuretic hormone (ADH) secretion
C. Decreased sympathetic nervous system activity
D. Increased urine production
Correct Answer: B. Increased antidiuretic hormone (ADH) secretion
Detailed Rationale
When dehydration occurs, plasma osmolarity increases and blood
volume decreases. The hypothalamus stimulates the posterior pituitary
,to release ADH, which increases water reabsorption in the kidneys,
reducing urine output and helping maintain circulating blood volume
and blood pressure.
Why the others are incorrect:
A: Aldosterone usually increases, not decreases.
C: Sympathetic activity increases during dehydration.
D: Urine production decreases.
ATI Tip: ADH = Retains Water
---
Question 2
Which cardiac valve prevents blood from flowing back into the left
atrium during ventricular contraction?
A. Tricuspid valve
B. Pulmonary valve
C. Mitral (bicuspid) valve
D. Aortic valve
,Correct Answer: C. Mitral (bicuspid) valve
Detailed Rationale
During systole, the left ventricle contracts, causing the mitral valve to
close and prevent blood from flowing backward into the left atrium.
Memory Aid
Right side = Tricuspid
Left side = Mitral (Bicuspid)
---
Question 3
Which electrolyte is primarily responsible for initiating skeletal muscle
contraction?
A. Sodium
B. Calcium
C. Potassium
, D. Chloride
Correct Answer: B. Calcium
Detailed Rationale
Calcium binds to troponin, causing tropomyosin to move away from
actin's binding sites. This allows actin and myosin to interact, producing
muscle contraction.
---
Question 4
A client has damage to the cerebellum. Which assessment finding
should the nurse expect?
A. Difficulty maintaining balance and coordination
B. Loss of speech comprehension
C. Complete paralysis of both legs
D. Inability to regulate body temperature
Correct Answer: A. Difficulty maintaining balance and coordination
practice test. Test 4 Question and Answers with
Rationales Top rated Latest Version
Question 1
A nurse is assessing a client with severe dehydration after several days
of vomiting. Which physiological response is expected to help maintain
blood pressure?
A. Decreased aldosterone secretion
B. Increased antidiuretic hormone (ADH) secretion
C. Decreased sympathetic nervous system activity
D. Increased urine production
Correct Answer: B. Increased antidiuretic hormone (ADH) secretion
Detailed Rationale
When dehydration occurs, plasma osmolarity increases and blood
volume decreases. The hypothalamus stimulates the posterior pituitary
,to release ADH, which increases water reabsorption in the kidneys,
reducing urine output and helping maintain circulating blood volume
and blood pressure.
Why the others are incorrect:
A: Aldosterone usually increases, not decreases.
C: Sympathetic activity increases during dehydration.
D: Urine production decreases.
ATI Tip: ADH = Retains Water
---
Question 2
Which cardiac valve prevents blood from flowing back into the left
atrium during ventricular contraction?
A. Tricuspid valve
B. Pulmonary valve
C. Mitral (bicuspid) valve
D. Aortic valve
,Correct Answer: C. Mitral (bicuspid) valve
Detailed Rationale
During systole, the left ventricle contracts, causing the mitral valve to
close and prevent blood from flowing backward into the left atrium.
Memory Aid
Right side = Tricuspid
Left side = Mitral (Bicuspid)
---
Question 3
Which electrolyte is primarily responsible for initiating skeletal muscle
contraction?
A. Sodium
B. Calcium
C. Potassium
, D. Chloride
Correct Answer: B. Calcium
Detailed Rationale
Calcium binds to troponin, causing tropomyosin to move away from
actin's binding sites. This allows actin and myosin to interact, producing
muscle contraction.
---
Question 4
A client has damage to the cerebellum. Which assessment finding
should the nurse expect?
A. Difficulty maintaining balance and coordination
B. Loss of speech comprehension
C. Complete paralysis of both legs
D. Inability to regulate body temperature
Correct Answer: A. Difficulty maintaining balance and coordination
