CABT Anatomy and Physiology Fundamentals 4

Question 1

Which hormone is produced by the adrenal medulla and plays a key role in the 'fight-or-flight' response?

Accepted Answer

Epinephrine

Answer

The adrenal medulla secretes epinephrine (adrenaline) and norepinephrine in response to sympathetic nervous system activation during stress.

Question 2

A pulse oximeter measures oxygen saturation using light absorption. Which property of hemoglobin makes this possible?

Accepted Answer

Oxyhemoglobin and deoxyhemoglobin absorb red and infrared light differently

Answer

Pulse oximeters exploit the different light absorption spectra of oxyhemoglobin (red light) and deoxyhemoglobin (infrared light) to calculate SpO2.

Question 3

Which of the following accurately describes the function of the blood-brain barrier (BBB)?

Accepted Answer

It selectively restricts the passage of substances between blood and brain tissue

Answer

The BBB, formed by tight junctions between brain capillary endothelial cells and supported by astrocyte endfeet, selectively controls what enters brain tissue.

Question 4

In a patient with a fractured femur, which artery is at greatest risk of injury due to its proximity to the bone in the femoral shaft?

Accepted Answer

Perforating branches of the deep femoral artery

Answer

Perforating branches of the profunda femoris (deep femoral artery) run close to the femoral shaft and are commonly injured in mid-shaft femur fractures.

Question 5

What is the role of the sinoatrial (SA) node in cardiac physiology?

Accepted Answer

It initiates the electrical impulse that sets the heart rate

Answer

The SA node, located in the right atrium, spontaneously depolarizes at 60–100 bpm, acting as the natural pacemaker of the heart.

(CABT) Certified Associate in Biomedical Technology Practice Test

(CABT) Certified Associate in Biomedical Technology Practice Test

CABT Anatomy and Physiology Fundamentals 4