ATI TEAS Science Questions

Correct Answer: C

Rationale: Schwann cells are the glial cells responsible for myelinating neurons in the peripheral nervous system (PNS). They form the myelin sheath around axons, which helps in the conduction of electrical impulses. Oligodendrocytes, on the other hand, myelinate neurons in the central nervous system (CNS). Astrocytes primarily provide support for neuronal function by regulating the chemical environment around neurons and maintaining the blood-brain barrier. Microglia are part of the immune response in the CNS, where they act as the resident macrophages, playing a role in immune surveillance and response to injury or disease. Therefore, the correct answer is Schwann cells (Choice C) as they specifically myelinate neurons in the PNS, differentiating them from the other cell types mentioned in the choices.

Correct Answer: C

Rationale: The correct function of the pons is to relay messages from the cortex to the cerebellum. The pons acts as a bridge between different brain regions, facilitating communication and coordination of movements. Choices A, B, and D are incorrect. The pons is not the center for emotion and motivation, does not control hormone production, and is not primarily responsible for involuntary actions like breathing. Understanding the role of the pons in relaying messages between brain regions is crucial for comprehending its function in the central nervous system.

Correct Answer: B

Rationale: The correct answer is 'B: Medial.' 'Medial' refers to a position closer to the midline of the body, while 'lateral' refers to a position further from the midline. 'Proximal' describes a position closer to the point of attachment or trunk of the body, while 'distal' refers to a position further away from the point of attachment or trunk.

Correct Answer: C

Rationale: The correct answer is C: Duodenum, jejunum, ileum. The small intestine is divided into three regions: the duodenum, jejunum, and ileum. The duodenum is the initial segment where most chemical digestion takes place. The jejunum and ileum follow the duodenum and are primarily responsible for nutrient absorption. Choice A is incorrect because the order is incorrect. Choice B is incorrect because the cecum is part of the large intestine, not the small intestine. Choice D is incorrect because the colon is part of the large intestine, not the small intestine.

Correct Answer: B

Rationale: The correct answer is B: White blood cell. White blood cells are the primary cells responsible for fighting infections and foreign invaders in the body. Red blood cells carry oxygen to tissues, platelets help in blood clotting to prevent excessive bleeding, and plasma is the liquid component of blood that carries cells and nutrients. White blood cells, also known as leukocytes, play a crucial role in the immune system by identifying and destroying pathogens, such as bacteria, viruses, and other harmful substances. Therefore, they are the key players in the body's defense against infections, making them the correct answer in this scenario. While red blood cells, platelets, and plasma have essential functions in the body, they are not primarily responsible for combating infections like white blood cells.