ATI TEAS 7 Science

Correct Answer: C

Rationale: The correct answer is C: Vitamin K. Vitamin K is essential for blood clotting as it helps in the synthesis of clotting factors. Without adequate vitamin K, the blood cannot clot properly, leading to excessive bleeding. Vitamin A (Choice A) is crucial for vision and immune function, not blood clotting. Vitamin C (Choice B) is important for collagen synthesis and immune function, not blood clotting. Vitamin D (Choice D) is essential for bone health and immune function, not blood clotting. Thus, the correct choice is Vitamin K as it plays a direct role in the blood clotting process.

Correct Answer: A

Rationale: The correct answer is A: Calcitonin. Calcitonin is produced by the thyroid gland and functions to lower blood calcium levels by promoting calcium deposition in bones and inhibiting calcium reabsorption in the kidneys. This hormone opposes the action of parathyroid hormone (PTH), which increases blood calcium levels by promoting calcium release from bones and increasing calcium reabsorption in the kidneys. Thyroxine is a thyroid hormone that regulates metabolism and growth, not calcium levels. Insulin is a hormone produced by the pancreas that regulates blood sugar levels, not calcium levels. Thus, A is the correct answer as it directly regulates calcium levels in the blood through its actions on bones and kidneys.

Correct Answer: B

Rationale: The correct answer is B: Alveoli. Alveoli are tiny air sacs in the lungs where the exchange of oxygen and carbon dioxide occurs during respiration. Oxygen from the air we breathe diffuses into the bloodstream, while carbon dioxide from the blood is released into the alveoli to be exhaled. The trachea (A) is a tube that carries air to and from the lungs, the bronchi (C) are branches of the trachea, and the diaphragm (D) is a muscle that helps with breathing but is not directly involved in gas exchange. Therefore, the alveoli are responsible for gas exchange in the respiratory system.

Correct Answer: D

Rationale: The correct answer is D because muscle tissue is indeed involved in all the functions listed. Muscles generate body heat through metabolism, stabilize joints by providing support and movement, and help maintain posture by keeping the body in an upright position. Therefore, muscle tissue plays a crucial role in all these functions. Choices A, B, and C are incorrect individually as they only represent a part of the functions that muscle tissue is involved in, whereas the correct answer encompasses all aspects of muscle function in the body.

Correct Answer: D

Rationale: The Golgi apparatus is responsible for modifying, sorting, and packaging proteins and lipids for transport within or outside the cell. It receives proteins from the endoplasmic reticulum for further processing. Option D is correct because it accurately describes the main functions of the Golgi apparatus. Option A is incorrect because the transport of proteins and lipids is primarily carried out by the endoplasmic reticulum. Option B is incorrect as the Golgi apparatus is not primarily for storing water and nutrients. Option C is incorrect because protein synthesis primarily occurs in the ribosomes, not the Golgi apparatus.