1. Which part of the brainstem controls heart rate and breathing?

A. Medulla oblongata
B. Pons
C. Midbrain
D. Thalamus

Correct answer: B

Rationale: The correct answer is B: Pons. The pons is a part of the brainstem located above the medulla oblongata and plays a crucial role in controlling vital functions such as heart rate and breathing. It contains neural circuits that regulate the rhythmic patterns of breathing and works in coordination with the medulla oblongata to ensure proper respiratory function. While the medulla oblongata is also involved in regulating these functions, the pons is more specifically responsible for fine-tuning and coordinating the activity of these essential processes.

2. What is the protective sac surrounding the testes in the male reproductive system?

A. Vas deferens
B. Scrotum
C. Epididymis
D. Urethra

Correct answer: B

Rationale: The correct answer is B: Scrotum. The scrotum is the protective sac surrounding the testes in the male reproductive system. It houses and protects the testes, helping to regulate their temperature for optimal sperm production. The vas deferens is a duct that carries sperm from the testes to the urethra. The epididymis is a coiled tube where sperm mature and are stored. The urethra is a tube that carries urine from the bladder and semen from the reproductive system. Therefore, the scrotum is the specific structure that directly surrounds and protects the testes in the male reproductive system.

3. Which property of a wave remains constant when it crosses a boundary between two different media?

A. Frequency
B. Wavelength
C. Amplitude
D. Speed

Correct answer: d

Rationale: The speed of a wave remains constant when it crosses a boundary between two different media, although its direction may change.

4. The tiny air sacs in the lungs where gas exchange takes place are called:

A. Bronchi
B. Trachea
C. Alveoli
D. Pleura

Correct answer: A

Rationale: The correct answer is C: 'Alveoli.' Alveoli are the tiny air sacs in the lungs where gas exchange takes place. Oxygen from the air is diffused into the blood, and carbon dioxide from the blood is diffused into the air in the alveoli. Bronchi (option A) are the large air passages that lead from the trachea into the lungs. Trachea (option B) is the windpipe that connects the larynx to the bronchi. Pleura (option D) is a thin membrane that surrounds the lungs and lines the chest cavity. Understanding these structures is essential for comprehending respiratory function and gas exchange in the human body.

5. A medication order is written as 3/4 of a tablet. If each tablet is 500mg, what is the equivalent dosage in milligrams?

A. 375mg
B. 425mg
C. 450mg
D. 475mg

Correct answer: A

Rationale: Multiply the tablet strength (500mg) by the fractional dose (3/4) to get 375 milligrams.

6. What happens when an atom loses an electron?

A. It becomes a molecule.
B. It gains a positive charge and becomes an ion.
C. It changes its element identity.
D. Nothing happens, it remains neutral.

Correct answer: B

Rationale: It gains a positive charge and becomes an ion. Losing an electron disrupts the charge balance, leaving the atom with more protons than electrons and a positive charge.