which is a posterior feature of the human leg

HESI A2

HESI A2 Anatomy and Physiology Practice Exam

1. Which is a posterior feature of the human leg?

A. Patella
B. Quadriceps sartorius
C. Triceps brachii
D. Achilles tendon

Correct answer: D

Rationale: The correct answer is the Achilles tendon. The Achilles tendon is a strong tendon located at the back of the human leg, connecting the calf muscles to the heel bone. This positioning makes it a posterior feature, situated at the rear of the leg. The patella, also known as the kneecap, is positioned at the front of the leg, making it an anterior feature. The quadriceps sartorius are muscles located in the front of the thigh, not at the back of the leg. Additionally, the triceps brachii is a muscle found in the upper arm, not in the leg, making it an incorrect choice.

2. Which type of muscle is under voluntary control?

A. Smooth muscle
B. Cardiac muscle
C. Skeletal muscle
D. Striated muscle

Correct answer: C

Rationale: The correct answer is C: Skeletal muscle. Skeletal muscle is under voluntary control, allowing individuals to consciously regulate its contractions for movement. Examples of skeletal muscle control include actions like walking, running, and lifting weights. Smooth muscle (choice A) and cardiac muscle (choice B) are both involuntary muscles, meaning they are not under conscious control. While skeletal muscle is striated (choice D), striated muscle is a broader category that includes both voluntary (skeletal) and involuntary (cardiac) muscles.

3. What is the function of the coronary artery?

A. It carries oxygenated blood to the heart muscle.
B. It carries deoxygenated blood to the lungs.
C. It distributes blood to the body.
D. It supplies blood to the heart muscle.

Correct answer: D

Rationale: The correct answer is D: 'It supplies blood to the heart muscle.' The coronary artery's main function is to supply oxygenated blood to the heart muscle, ensuring that the heart receives the necessary nutrients and oxygen it needs to function properly. Choices A, B, and C are incorrect because the coronary artery specifically delivers oxygenated blood to the heart muscle, not deoxygenated blood to the lungs or blood to the rest of the body.

4. Beriberi is a disease caused by a lack of ___________.

A. thiamine
B. vitamin C
C. niacin
D. protein

Correct answer: A

Rationale: Beriberi is a disease caused by a deficiency of thiamine, also known as vitamin B1. Thiamine is essential for the proper functioning of the nervous system and energy metabolism in the body. Without enough thiamine, individuals may develop symptoms such as weakness, fatigue, nerve damage, and heart problems, which are characteristic of beriberi. Vitamin C (choice B), niacin (choice C), and protein (choice D) deficiencies can cause other health issues but are not directly related to beriberi.

5. Where are B-lymphocytes produced?

A. Thymus
B. Red bone marrow
C. Lymph nodes
D. Spleen

Correct answer: B

Rationale: B-lymphocytes are produced in the red bone marrow. The red bone marrow is the primary site for B-cell development, where they mature before entering the circulation. The thymus is responsible for T-lymphocyte maturation, not B-lymphocytes. Lymph nodes and spleen play roles in immune responses but are not the primary sites for B-lymphocyte production.