NRCMA Anatomy and Physiology 2

Question 1

The sinoatrial (SA) node is known as the heart's pacemaker because it:

Accepted Answer

Initiates the electrical impulse that triggers each heartbeat

Answer

The SA node, located in the right atrium, spontaneously generates electrical impulses at 60–100 times per minute, setting the normal heart rate.

Question 2

The nephron is the functional unit of which organ?

Accepted Answer

Kidney

Answer

Each kidney contains approximately one million nephrons, which filter blood, reabsorb nutrients, and produce urine.

Question 3

Which vitamin is synthesized by the skin upon exposure to ultraviolet B (UVB) radiation?

Accepted Answer

Vitamin D

Answer

Ultraviolet B radiation converts 7-dehydrocholesterol in the skin to previtamin D3, which is then converted to active vitamin D (calcitriol) in the liver and kidneys.

Question 4

The function of the cerebellum is primarily to:

Accepted Answer

Regulate voluntary movement, coordination, and balance

Answer

The cerebellum coordinates voluntary movements, maintains balance and posture, and refines motor skills through feedback from muscles, joints, and the vestibular system.

Question 5

Which hormone is released by the posterior pituitary and promotes water reabsorption by the kidneys?

Accepted Answer

Antidiuretic hormone (ADH/vasopressin)

Answer

ADH (antidiuretic hormone, also called vasopressin) is released from the posterior pituitary in response to high blood osmolality, stimulating renal water reabsorption to concentrate urine.

(NRCMA) Nationally Registered Certified Medical Assistant Practice Test

(NRCMA) Nationally Registered Certified Medical Assistant Practice Test

NRCMA Anatomy and Physiology 2