ATI TEAS Science Questions

Correct Answer: B

Rationale: The myelin sheath serves to insulate neurons and accelerate the transmission of electrical signals along the axon. This insulation helps in the efficient conduction of nerve impulses by preventing signal loss or leakage. Choice A is incorrect because the myelin sheath does not transmit electrical impulses itself but rather helps in the conduction. Choice C is incorrect as the myelin sheath is not responsible for producing neurotransmitters. Choice D is also incorrect as the primary function of the myelin sheath is not to protect the neuron from damage. Therefore, the correct answer is B, as it accurately describes the function of the myelin sheath in a neuron.

Correct Answer: C

Rationale: The correct answer is C: Virus. Viruses are not considered living organisms because they lack cellular structure. Instead, they are composed of nucleic acids (either DNA or RNA) enclosed in a protein coat called a capsid. Bacteria (choice A), fungus (choice B), and protozoa (choice D) are all living organisms with cellular structures, unlike viruses. Therefore, they are incorrect choices for this question.

Correct Answer: C

Rationale: Carbohydrates are broken down into glucose during digestion, providing energy for cellular processes through glycolysis and cellular respiration. Glucose is a primary source of energy for cells, and its breakdown is essential for powering various cellular activities. Lipids are broken down into fatty acids and glycerol, not glucose. Proteins are broken down into amino acids and are not a direct source of glucose. Nucleic acids are not broken down into glucose for energy production.

Correct Answer: B

Rationale: Smooth muscle is the correct type of muscle found in the walls of hollow organs like the intestines. It is responsible for movements such as peristalsis, aiding in the movement of food and other materials through the digestive system. Cardiac muscle (Choice A) is found in the heart and is responsible for the heart's contractions, not in hollow organs like the intestines. Skeletal muscle (Choice C) is attached to bones and responsible for voluntary movements, not in hollow organ walls. Voluntary muscle (Choice D) is another term for skeletal muscle, which is under conscious control, unlike smooth muscle in hollow organ walls.

Correct Answer: B

Rationale: The main function of the skeletal system is to provide structural support for the body, protect internal organs, facilitate movement, and produce blood cells in the bone marrow. Choice A, 'To regulate blood pressure,' is incorrect as blood pressure regulation is primarily controlled by the circulatory and endocrine systems. Choice C, 'To produce hormones,' is incorrect as hormone production is mainly carried out by the endocrine system. Choice D, 'To fight infection,' is incorrect as the immune system is responsible for fighting infections, not the skeletal system.