ATI TEAS Practice Science Test

Correct Answer: B

Rationale: The correct answer is B: The plant left outside in normal conditions serves as the control of the experiment. This is because the control group in an experiment remains unchanged and is used as a baseline for comparison. In this case, the plant left outside in normal conditions is the control as it is not subjected to any experimental manipulation, unlike the other tropical plants in the greenhouse. By comparing the growth of the plants in the greenhouse to the plant left outside, any changes in plant height can be attributed to the varying humidity levels, thus allowing for a valid comparison. Choice A is incorrect because plant height for each tropical plant is the experimental variable being measured, not the control. Choice C is incorrect as humidity level readings in the greenhouse are part of the experimental conditions, not the control. Choice D is incorrect because the amount of time used to study plant height is not the control of the experiment; it is the duration of the study.

Correct Answer: C

Rationale: The correct answer is C: Hypothalamus. The hypothalamus is a major structure of the limbic system responsible for regulating various essential functions like emotions, behavior, and physiological processes. It plays a crucial role in the control of thirst, hunger, body temperature, and hormonal regulation. The brainstem (A) is involved in basic life functions like breathing and heart rate, but it is not a part of the limbic system. The spinal cord (B) primarily functions in transmitting sensory and motor signals but is not directly related to the limbic system. The cerebral cortex (D) is responsible for higher-order thinking, sensory processing, and motor functions but is not a major structure of the limbic system.

Correct Answer: A

Rationale: The correct answer is A: Flagellum. Cells rely on flagella for movement because flagella are whip-like structures that enable cells to propel themselves through fluid environments. Flagella are composed of microtubules, which provide structural support and enable movement through their bending and contracting motion. Microtubules alone (B) do not facilitate movement; they serve as a scaffold within cells. Pili (C) are short, hair-like structures used for attachment rather than movement. Vesicles (D) are membrane-bound sacs involved in transportation within cells, not in cell movement. Therefore, flagellum is the most suitable structure for cellular movement.

Correct Answer: A

Rationale: The hypodermis is primarily composed of adipose tissue, which is a type of connective tissue. Adipose tissue serves as a layer of insulation and energy storage in the body. It helps regulate body temperature and provides cushioning for organs. Adipose tissue is the main component of the hypodermis, making choice A the correct answer. Choices B, C, and D are incorrect because the hypodermis is not primarily composed of regular connective tissue, epithelial tissue, or muscle tissue.

Correct Answer: A

Rationale: The correct answer is A: Cranial and spinal. The dorsal cavity is divided into two subdivisions: the cranial cavity, which contains the brain, and the spinal cavity, which houses the spinal cord. This division corresponds to the anatomical locations of these structures within the back of the human body. Explanation: 1. The cranial cavity is located in the skull, specifically protecting the brain. 2. The spinal cavity runs through the vertebral column, safeguarding the spinal cord. 3. These subdivisions are anatomically and functionally distinct, housing vital components of the central nervous system. Summary: B: Dorsal and ventral - Incorrect. Dorsal and ventral refer to the front and back sides of the body, not specific cavities within the back. C: Lateral and proximal - Incorrect. Lateral and proximal describe directions in relation to the body, not cavities within the back. D: Inferior and superior - Incorrect. Inferior and superior