Correct Answer: C

Rationale: In this scenario, where a child complains of heavy breathing even when relaxing and has no history of respiratory problems, the most likely issue is hyperventilation. Hyperventilation is an abnormal breathing pattern where a person breathes in excess of the body's requirements. It can be triggered by stress, anxiety, panic attacks, or lower-than-normal carbon dioxide levels in the blood. Unlike asthma, a blood clot, or exercising too hard, hyperventilation fits the symptoms described and is more common in individuals without a history of respiratory problems.

Correct Answer: B

Rationale: The correct answer is B. Glial cells in the CNS include astrocytes, microglia, ependymal cells, and oligodendrocytes. Schwann cells and satellite cells are found in the PNS. Astrocytes are the most abundant type of glial cells and are involved in nutrient support, repair, and maintenance of the extracellular environment. Microglia are the resident immune cells of the CNS, playing a role in immune defense. Ependymal cells line the ventricles of the brain and the central canal of the spinal cord, contributing to the production and circulation of cerebrospinal fluid. Oligodendrocytes are responsible for producing myelin, which insulates axons in the CNS. Understanding the specific functions of each type of glial cell is essential in grasping the complexity of the central nervous system's support and protective mechanisms.

Correct Answer: A

Rationale: The primary processes involved in breathing are inspiration (inhaling air) and expiration (exhaling air). Inspiration is the process of taking air into the lungs, while expiration is the process of expelling air from the lungs. These two phases are crucial for gas exchange, where oxygen is taken in during inspiration and carbon dioxide is expelled during expiration. Choices B, C, and D are incorrect as they either combine inspiration with respiration or include unrelated processes like respiration and circulation. Therefore, the correct pair of processes involved in breathing is A, inspiration and expiration.

Correct Answer: B

Rationale: Oxygenated blood flows from the lungs to the left atrium, then to the left ventricle, and is pumped out through the aorta to the body. This pathway ensures efficient oxygen delivery to the body's tissues and organs. Choice A is incorrect as oxygenated blood does not flow directly from the heart to the brain. Choice C is incorrect as it suggests a route from the body to the right atrium and then to the lungs, which is the pathway for deoxygenated blood. Choice D is incorrect as it describes a direct pathway from the left atrium to the aorta, skipping the left ventricle, which is essential for pumping blood to the body.

Correct Answer: C

Rationale: The correct answer is C. The large intestine absorbs water, vitamin K, bile salts, sodium, and chloride ions. It helps in maintaining the body's water and electrolyte balance, and also plays a role in absorbing certain vitamins and nutrients such as vitamin K. Choices A, B, and D are incorrect because proteins, carbohydrates, vitamins A, D, E, and K are primarily absorbed in the small intestine, not the large intestine.