ATI TEAS 7 Science Practice Test

Correct Answer: C

Rationale: The mass of the ball would be an appropriate control variable for this experiment. By keeping the mass constant, you can ensure that any observed effects are not due to variations in mass but rather to the manipulated independent variable. Controlling the mass helps isolate and identify the true impact of the independent variable being studied. Choices A, B, and D are incorrect. The period and length of the string are more likely to be independent variables or factors being manipulated in the experiment. The color of the ball is considered an extraneous variable that is not typically controlled for in this type of experiment.

Correct Answer: B

Rationale: The correct answer is B, 'Stomach.' The stomach is an organ of the digestive system responsible for breaking down food through mechanical and chemical digestion. In contrast, the thyroid, intestines, and pancreas are glands. The thyroid gland regulates metabolism through hormone secretion, the intestines aid in digestion and nutrient absorption, and the pancreas secretes digestive enzymes and hormones. Therefore, the stomach is functionally different from the other options as it is an organ involved in digestion, while the others are glands with specific secretory functions.

Correct Answer: D

Rationale: Enzymes are large molecules that act as catalysts, accelerating chemical reactions by lowering the activation energy required for the reactions to occur. In the context of biological reactions, enzymes function as catalysts, not suppressors, triggers, or targets. The use of 'large' and 'catalysts' accurately describes the nature and role of enzymes in facilitating biological processes.

Correct Answer: C

Rationale: The correct answer is C: Pulmonary artery. The pulmonary artery carries deoxygenated blood from the heart to the lungs for oxygenation. This blood is considered the least oxygenated in the body as it has just returned from circulating through the body's tissues and is in need of oxygen replenishment. Choice A, the aorta, is incorrect as it carries oxygenated blood from the heart to the rest of the body. Choice B, the vena cava, carries deoxygenated blood from the body back to the heart. Choice D, the femoral vein, also carries deoxygenated blood back to the heart from the lower extremities.

Correct Answer: B

Rationale: The correct responsibility of the integumentary system is to act as a barrier that blocks pathogens from entering the body, thus helping to prevent diseases and infections. This function serves as the first line of defense for the body against external threats. Choices A, C, and D are incorrect. Choice A is a function of the circulatory system, not the integumentary system. Choice C relates to the lymphatic system, not the integumentary system. Choice D involves the endocrine system, not the integumentary system.