ATI TEAS 7 Science

Correct Answer: B

Rationale: The correct answer is B: Insulin. Insulin is responsible for regulating blood sugar levels by facilitating the uptake of glucose into cells for energy production and storage. It helps lower blood sugar levels by promoting glucose utilization. Thyroxine (A) regulates metabolism, adrenaline (C) is involved in the fight-or-flight response, and cortisol (D) regulates stress response and metabolism, but they do not directly regulate blood sugar levels like insulin does.

Correct Answer: B

Rationale: The correct answer is B: In a covalent bond, the shared electrons spend more time closer to the more electronegative atom. This is because the more electronegative atom attracts the electrons more strongly, causing them to be closer to that atom. This creates a partial negative charge on the more electronegative atom and a partial positive charge on the other atom. This distribution of electron density contributes to the stability of the covalent bond. Choices A, C, and D are incorrect because: A: Are completely transferred to one atom - This describes an ionic bond, not a covalent bond. C: Remain equidistant between the two atoms - Shared electrons in a covalent bond are not equidistant but are closer to one atom. D: Do not influence the bond strength - The distribution of shared electrons significantly influences the strength and properties of a covalent bond.

Correct Answer: B

Rationale: Peristalsis is the correct answer. It is the term for the involuntary muscle contractions that move food through the digestive tract. These contractions help propel food along the digestive system. Segmentation is the process of breaking down food by mixing it with digestive juices. Chyme is the semi-fluid mass of partly digested food in the stomach and intestines. Emulsification is the breakdown of fats into smaller droplets for easier digestion. But none of these terms specifically refer to the muscle contractions that move food through the digestive tract like peristalsis does.

Correct Answer: C

Rationale: The correct answer is C: Testes. The testes are responsible for producing testosterone, a male sex hormone. They contain specialized cells called Leydig cells that produce testosterone. The adrenal glands (A) produce hormones like cortisol and adrenaline, not testosterone. The pituitary gland (B) regulates hormone production but does not directly produce testosterone. The pancreas (D) produces insulin and other digestive enzymes, not testosterone. Therefore, the testes are the correct answer for testosterone production.

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.