Biology Test Biology Human Anatomy & Physiology 3 — Questions and Answers
Question 1: Which layer of the skin contains melanocytes that produce melanin?
- Stratum corneum
- Stratum lucidum
- Stratum basale (Correct answer)
- Stratum granulosum
Correct answer: Stratum basale
Melanocytes in the stratum basale produce melanin, which protects deeper cells from UV radiation.
Question 2: The bicuspid (mitral) valve controls blood flow between which two chambers?
- Right atrium and right ventricle
- Left ventricle and aorta
- Left atrium and left ventricle (Correct answer)
- Right ventricle and pulmonary artery
Correct answer: Left atrium and left ventricle
The bicuspid valve prevents backflow of blood from the left ventricle into the left atrium during systole.
Question 3: Which region of the brain regulates body temperature, hunger, and the release of pituitary hormones?
- Thalamus
- Hypothalamus (Correct answer)
- Cerebellum
- Medulla oblongata
Correct answer: Hypothalamus
The hypothalamus integrates autonomic functions and controls the pituitary gland through releasing and inhibiting hormones.
Question 4: Surfactant, which reduces surface tension in alveoli, is produced by which cell type?
- Type I pneumocytes
- Type II pneumocytes (Correct answer)
- Goblet cells
- Alveolar macrophages
Correct answer: Type II pneumocytes
Type II pneumocytes secrete pulmonary surfactant, preventing alveolar collapse during expiration.
Question 5: What term describes the movement of a limb away from the midline of the body?
- Adduction
- Flexion
- Abduction (Correct answer)
- Extension
Correct answer: Abduction
Abduction moves a limb laterally away from the body's midline, such as raising an arm to the side.
Question 6: Which enzyme in saliva begins the chemical digestion of carbohydrates?
- Pepsin
- Lipase
- Amylase (Correct answer)
- Trypsin
Correct answer: Amylase
Salivary amylase (ptyalin) begins breaking down starch into maltose in the mouth.
Question 7: The trachea bifurcates at the carina to form the two primary bronchi at approximately which vertebral level?
- C7
- T4-T5 (Correct answer)
- L1
- T10
Correct answer: T4-T5
The trachea divides into left and right primary bronchi at the carina, located at the level of T4-T5.
Biology Test Biology Human Anatomy & Physiology 3
Which layer of the skin contains melanocytes that produce melanin?