UExcel Anatomy and Physiology 5

Question 1

Which bone is NOT part of the axial skeleton?

Accepted Answer

Scapula

Answer

The scapula (shoulder blade) is part of the appendicular skeleton, while the sternum, sacrum, and hyoid are axial skeleton components.

Question 2

The hypothalamus regulates body temperature primarily by acting as a:

Accepted Answer

Thermostat set point

Answer

The hypothalamus acts as the body's thermostat, comparing core temperature to a set point and triggering corrective responses (shivering, sweating).

Question 3

In a negative feedback loop controlling thyroid hormone levels, elevated T3 and T4 would cause:

Accepted Answer

Decreased TSH secretion from the anterior pituitary

Answer

High T3/T4 levels feed back to inhibit TSH release from the anterior pituitary and TRH from the hypothalamus, reducing further thyroid stimulation.

Question 4

Which type of synovial joint allows the widest range of motion, including flexion, extension, abduction, and rotation?

Accepted Answer

Ball-and-socket joint

Answer

Ball-and-socket joints (e.g., shoulder, hip) allow multiaxial movement including flexion, extension, abduction, adduction, and rotation.

Question 5

Which protein complex in the thick filaments of skeletal muscle contains the ATPase activity needed for muscle contraction?

Accepted Answer

Myosin

Answer

Myosin heads possess ATPase activity, hydrolyzing ATP to generate the power stroke that pulls actin filaments during contraction.

UExcel Practice Test