ATI TEAS Science Practice Test

Correct Answer: D

Rationale: Potency refers to a cell's potential to differentiate into different cell types. It is not related to the cell's ability to survive (Choice A), move (Choice B), or divide rapidly (Choice C). Stem cells, for example, exhibit varying degrees of potency based on their capacity to give rise to various cell types. Therefore, the correct answer is D as it accurately defines the concept of potency in cells.

Correct Answer: A

Rationale: The correct answer is A: Negative feedback loop. Negative feedback loops work to inhibit the stimulus or reduce the deviation from a set point, maintaining homeostasis by counteracting any changes from the norm. In this case, the negative feedback loop acts to minimize any deviation from the body's internal balance, ensuring stability and optimal functioning. Choice B, a positive feedback loop, amplifies the stimulus or deviation, moving systems away from homeostasis. Choice C, an inhibitory feedback loop, is not a commonly recognized term in the context of feedback mechanisms. Choice D, a stimulating feedback loop, is not a standard term and does not accurately describe a feedback loop's role in maintaining homeostasis.

Correct Answer: A

Rationale: The correct answer is A: Sagittal/Median Plane. This plane divides the body into left and right halves. The Frontal/Coronal Plane (choice B) divides the body into front and back, while the Transverse/Cross-Section Plane (choice C) divides it into top and bottom. The Horizontal Plane (choice D) divides the body into upper and lower portions. Understanding these planes is essential in anatomy as they help describe the orientation and relationships of body structures.

Correct Answer: C

Rationale: The correct answer is C: Parathyroid glands. The parathyroid glands are responsible for regulating calcium levels in the body. They produce parathyroid hormone (PTH), which helps control calcium levels in the blood by acting on the bones, kidneys, and intestines. The other options, such as the osteotoid gland, pineal gland, and thymus gland, do not play a significant role in calcium regulation. The osteotoid gland is a fictitious term, the pineal gland is involved in regulating sleep-wake cycles and producing melatonin, and the thymus gland is part of the immune system and plays a role in T-cell maturation.

Correct Answer: B

Rationale: To prepare 250 mL of a 50 M solution of HCl, the formula V1 x C1 = V2 x C2 is used, where V1 is the volume of the stock solution, C1 is the concentration of the stock solution, V2 is the final volume of the desired solution, and C2 is the final concentration of the desired solution. Given V1 x 0 M = 250 mL x 50 M, solving for V1 results in V1 = (250 mL x 50 M) / 0 M = 32 mL. Therefore, 32 mL of the 0 M stock solution of HCl needs to be added to water to create a 250 mL solution of 50 M HCl. Choices A, C, and D are incorrect because they do not represent the accurate volume required for the dilution calculation based on the given concentrations and volumes in the problem.