ATI TEAS 7 Science

Correct Answer: C

Rationale: The primary function of the lymphatic system is to fight infection and remove excess fluid. Lymph nodes contain white blood cells that help fight pathogens. Lymphatic vessels collect excess fluid from tissues and transport it back to the bloodstream, aiding in immune response. Other choices are incorrect because A: Oxygen transport is primarily done by the circulatory system, B: Blood filtration is mainly carried out by the kidneys, and D: Hormone transport is primarily through the circulatory system.

Correct Answer: B

Rationale: The correct answer is B: Thyroxine. Thyroxine is a hormone produced by the thyroid gland that plays a key role in regulating metabolism. It controls the body's metabolic rate, impacting energy levels and weight. Adrenaline (A) is produced by the adrenal glands and is involved in the fight-or-flight response. Cortisol (C) is produced by the adrenal glands and is known as the stress hormone. Insulin (D) is produced by the pancreas and regulates blood sugar levels, not metabolism. Thyroxine directly influences metabolism, making it the correct choice.

Correct Answer: C

Rationale: The correct answer is C: Emulsify fats. Bile helps emulsify fats by breaking them down into smaller droplets, increasing the surface area for enzymes to digest fats. This aids in the absorption of fats and fat-soluble vitamins in the small intestine. Choice A is incorrect because bile does not break down carbohydrates. Choice B is incorrect as bile does not break down proteins. Choice D is incorrect because bile does not neutralize stomach acid; rather, it helps with fat digestion in the small intestine.

Correct Answer: C

Rationale: The correct answer is C: Nucleus. The nucleus is responsible for controlling the activities of the cell because it houses the cell's DNA, which contains instructions for cellular functions. It regulates gene expression and controls the production of proteins. The Golgi apparatus (choice A) is involved in processing and packaging proteins. Mitochondria (choice B) are responsible for energy production. Ribosomes (choice D) are responsible for protein synthesis. However, the nucleus is the main organelle that directly regulates and controls the activities of the cell.

Correct Answer: B

Rationale: The correct answer is B: 23. In humans, each normal cell contains 23 pairs of chromosomes, making a total of 46 chromosomes. The pairs consist of one chromosome from each parent, ensuring genetic diversity. Choices A, C, and D are incorrect because they do not reflect the accurate number of chromosome pairs in a human cell. Option A (46) is the total number of chromosomes, not pairs. Option C (64) and D (32) are not the correct numbers of chromosome pairs in a human cell.