ATI TEAS Science Questions

Correct Answer: B

Rationale: The correct answer is B: Adipose and areolar connective tissue. The hypodermis, also known as the subcutaneous layer, is primarily composed of adipose (fat) and areolar (loose) connective tissue. These tissues provide insulation, cushioning, and energy storage. Epithelial tissue (Choice A) is not a significant component of the hypodermis, as it is mainly found in the epidermis and lining of internal organs. Collagen fibers (Choice C) are more abundant in the dermis, providing strength and support. Dense connective tissue (Choice D) is also present in the dermis but is not a major component of the hypodermis.

Correct Answer: B

Rationale: Silicon has an atomic number of 14, indicating it has 14 protons. The atomic mass of 28.1 AMU accounts for both protons and neutrons in the nucleus. By subtracting the atomic number from the atomic mass, we can estimate the number of neutrons in the atom. Thus, 28.1 - 14 = 14 neutrons. Choice A is incorrect as it represents the total atomic mass, not the number of neutrons. Choice C is incorrect; it is the atomic number (protons) rather than the number of neutrons. Choice D is incorrect as it is a value that does not reflect the number of neutrons in the silicon atom.

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: A

Rationale: The diastole cycle in the heart refers to the relaxation phase, where the heart chambers relax and fill with blood. This phase is crucial for the heart to refill and prepare for the next contraction (systole), which pumps blood out of the heart. Therefore, the correct answer is choice A, 'Relaxation of the heart.' Choices B, C, and D are incorrect in the context of cardiac physiology. Choice B, 'Contraction of the heart,' refers to systole, the phase of heart contraction. Choice C, 'Pulse rate of the heart,' is related to the number of heartbeats per minute, not the diastole cycle specifically. Choice D, 'Blood circulation,' is a broader term that encompasses the entire circulatory system rather than focusing on the heart's specific relaxation phase.

Correct Answer: A

Rationale: Blood vessels are indeed part of the cardiovascular system. They are crucial components that facilitate blood circulation by carrying blood throughout the body. The cardiovascular system consists of the heart, blood vessels (arteries, veins, and capillaries), and blood. Blood vessels play a vital role in delivering oxygen and nutrients to tissues and removing waste products. The brain, kidneys, and lungs are not part of the cardiovascular system; instead, they belong to other body systems. The brain is part of the nervous system, kidneys are part of the urinary system, and lungs are part of the respiratory system. Therefore, the correct answer is blood vessels (Choice A). Choices B, C, and D are incorrect as they are not components of the cardiovascular system but belong to different body systems.