teas 7 practice test free science - Nurselytic

Correct Answer: B

Rationale: Passive transport refers to the movement of molecules across a cell membrane without the input of energy. Diffusion of small molecules across a concentration gradient is a classic example of passive transport, as it occurs spontaneously from an area of high concentration to an area of low concentration. Active transport (option
A) requires energy input in the form of ATP to move substances against their concentration gradient. Movement of large molecules using vesicles (option
C) involves processes like endocytosis and exocytosis that require energy in the form of ATP. Endocytosis of particles into the cell (option
D) is an active process that requires energy expenditure by the cell to engulf and internalize extracellular substances.

Correct Answer: C

Rationale: The correct answer is C: Epinephrine (adrenaline). Epinephrine is produced by the adrenal medulla and is responsible for preparing the body for a stressful situation. It increases heart rate, dilates airways, and mobilizes energy stores to help the body respond to a fight-or-flight scenario. Testosterone (
Choice
A) is a sex hormone produced by the testes in males and in smaller amounts by the ovaries in females, not by the adrenal medulla. Cortisol (
Choice
B) is a stress hormone produced by the adrenal cortex, not the adrenal medulla. Growth hormone (
Choice
D) is produced by the pituitary gland and is involved in growth, metabolism, and various bodily functions, not by the adrenal medulla.

Correct Answer: B

Rationale: The primary function of the lymphatic system is to remove excess fluids, waste products, and toxins from tissues. It maintains fluid balance and supports the immune system by transporting lymph, which contains white blood cells, throughout the body.
Choice A is incorrect as nutrient transport is primarily handled by the circulatory system.
Choice C is incorrect because red blood cells are produced in the bone marrow, not the lymphatic system.
Choice D is incorrect as the regulation of body temperature is mainly controlled by the endocrine system and thermoregulatory mechanisms in the body.
Therefore, the correct answer is B.

Correct Answer: A

Rationale: The correct answer is the right atrium. The right atrium receives deoxygenated blood from the body through the superior and inferior vena cava. It then pumps this deoxygenated blood to the lungs via the pulmonary artery for oxygenation. The left atrium receives oxygenated blood from the lungs and pumps it to the left ventricle. The right ventricle receives oxygen-poor blood from the right atrium and pumps it to the lungs. The left ventricle receives oxygenated blood from the left atrium and pumps it to the rest of the body.

Correct Answer: A

Rationale: The correct statement is that atomic radius increases down a group and decreases across a period. When moving down a group, additional electron shells increase the distance from the nucleus, leading to larger atomic radii. On the other hand, when moving across a period, the number of electron shells remains constant, but the increasing nuclear charge pulls electrons closer, resulting in smaller radii.
Choice B is incorrect because atomic radius does not decrease down a group and increase across a period.
Choice C is incorrect because atomic radius does not remain constant; it exhibits specific trends.
Choice D is incorrect because atomic radius follows predictable trends based on the periodic table structure, rather than fluctuating unpredictably.