which parts of the heart are separated by the mitral valve

HESI A2

Anatomy HESI A2

1. Which parts of the heart are separated by the mitral valve?

A. Left atrium and right atrium
B. Right atrium and right ventricle
C. Left ventricle and right ventricle
D. Left atrium and left ventricle

Correct answer: D

Rationale: The mitral valve, also known as the bicuspid valve, separates the left atrium and the left ventricle of the heart. Its primary function is to prevent the backflow of blood from the left ventricle to the left atrium during the heart's contraction. Therefore, option D, 'Left atrium and left ventricle,' is the correct answer. Choices A, B, and C are incorrect because they do not represent the parts separated by the mitral valve.

2. Which part of the brain controls breathing and heart rate?

A. Cerebrum
B. Medulla oblongata
C. Cerebellum
D. Hypothalamus

Correct answer: B

Rationale: The medulla oblongata, located in the brainstem, plays a crucial role in controlling vital functions such as breathing, heart rate, and blood pressure. It serves as the control center for automatic functions necessary for survival, making it the correct choice in this scenario. The cerebrum is responsible for higher brain functions like thinking and voluntary movements, so it does not control basic physiological functions like breathing and heart rate. The cerebellum is mainly involved in coordination and balance, while the hypothalamus regulates body temperature, hunger, and thirst, but not specifically breathing and heart rate.

3. Which chamber of the heart is the strongest and largest?

A. Left atrium
B. Right atrium
C. Right ventricle
D. Left ventricle

Correct answer: D

Rationale: The left ventricle is the largest and most powerful chamber of the heart. It receives oxygenated blood from the left atrium and pumps it out to the body through the aorta, providing the body's tissues with vital oxygen and nutrients. The left atrium primarily acts as a receiving chamber for oxygenated blood from the lungs. The right atrium receives deoxygenated blood from the body, while the right ventricle pumps this blood to the lungs for oxygenation. Therefore, the correct answer is the left ventricle, as it is responsible for pumping oxygenated blood to the body.

4. How does the endocrine system work with the reproductive system?

A. The reproductive system transforms minerals into useful nutrients.
B. The endocrine system determines the sex of the embryo.
C. The reproductive system controls the growth of secondary sex organs.
D. The endocrine system produces chemicals that regulate sexual function.

Correct answer: D

Rationale: The correct answer is D. The endocrine system plays a vital role in the regulation of sexual functions within the reproductive system. It produces hormones that are responsible for various functions, such as the development of secondary sex characteristics, production of gametes (sperm and egg cells), and the regulation of the menstrual cycle. These hormones are crucial for the proper functioning and coordination of the reproductive system, ensuring the successful reproduction and maintenance of reproductive health. Choices A, B, and C are incorrect because the reproductive system is not primarily responsible for transforming minerals into nutrients, determining the sex of the embryo, or controlling the growth of secondary sex organs. These functions are mainly regulated by the endocrine system in coordination with the reproductive system.

5. What does trypsin break down in the body?

A. Fat
B. Starch
C. Proteins
D. Nucleic acids

Correct answer: C

Rationale: Trypsin is an enzyme that specifically breaks down proteins into smaller peptides by hydrolyzing peptide bonds. It is a key enzyme involved in the digestion of proteins in the body, particularly in the small intestine where it helps in the final stages of protein digestion. Choices A, B, and D are incorrect because trypsin does not break down fats, starch, or nucleic acids; its primary function is the digestion of proteins.