1. The dome-shaped muscular structure that separates the chest cavity from the abdominal cavity is the:

A. Diaphragm
B. Sternum
C. Pericardium
D. Trachea

Correct answer: A

Rationale: The correct answer is A: Diaphragm. The diaphragm is a dome-shaped muscular structure that plays a crucial role in respiration by contracting and flattening during inhalation to increase the volume of the thoracic cavity, allowing the lungs to expand and fill with air. It separates the chest cavity (thoracic cavity) from the abdominal cavity. The sternum (B) is a flat bone in the center of the chest, the pericardium (C) is a double-layered sac that surrounds the heart, and the trachea (D) is the windpipe that connects the larynx to the bronchi. Therefore, the diaphragm is the correct answer in this case.

2. Which of the following is NOT a function of the cardiovascular system?

A. Transporting oxygen to cells
B. Maintaining blood pressure
C. Carrying waste products to the kidneys for removal
D. Initiating the immune response

Correct answer: D

Rationale: The cardiovascular system is responsible for transporting oxygen to cells (option A), maintaining blood pressure (option B), and carrying waste products to the kidneys for removal (option C). However, initiating the immune response (option D) is not a function of the cardiovascular system. The immune response is primarily carried out by the immune system, which includes organs like the spleen and lymph nodes. While the cardiovascular system does play a role in immune function by transporting immune cells and antibodies, it is not responsible for initiating the immune response. Therefore, option D is the correct answer.

3. Which of the following is an example of a polymer?

A. Methane
B. Ethanol
C. Polyethylene
D. Acetic acid

Correct answer: C

Rationale: Polyethylene is a polymer, consisting of a large number of repeating ethylene units. The other choices represent small organic compounds.

4. Which type of waves exhibit both longitudinal and transverse motion?

A. Electromagnetic waves
B. Surface waves
C. Mechanical waves
D. Sound waves

Correct answer: b

Rationale: Surface waves, like those on water surfaces, exhibit both longitudinal and transverse motion.

5. The formula for calculating ideal body weight (IBW) for men is IBW (kg) = 50 + 2.3 * (height in cm - 150). If a man is 180cm tall, what is his ideal body weight?

A. 68kg
B. 71kg
C. 74kg
D. 77kg

Correct answer: C

Rationale: Substitute the man's height (180cm) into the formula: IBW = 50 + 2.3 * (180 - 150) = 74kg.

6. The muscular diaphragm plays a vital role in respiration. When it contracts, it:

A. Increases lung volume for inhalation
B. Decreases lung volume for exhalation
C. Filters dust and particles from inhaled air
D. Produces mucus to lubricate the airways

Correct answer: A

Rationale: The diaphragm is a crucial muscle involved in respiration. When the diaphragm contracts, it flattens and moves downwards, increasing the volume in the thoracic cavity. This expansion creates a negative pressure in the lungs, causing air to rush in during inhalation. Therefore, option A, 'Increases lung volume for inhalation,' is the correct answer. The diaphragm's contraction facilitates the breathing process by creating space for the lungs to expand and take in air, making it essential for proper respiration.