which of the following is not an example of a homeostatic mechanism

ATI TEAS 7

ATI TEAS Science Test

1. Which of the following is NOT an example of a homeostatic mechanism?

A. Shivering when the body temperature falls.
B. Increasing heart rate when blood pressure is low.
C. Weight gain when consuming excess calories.
D. Secreting insulin to decrease blood sugar concentration.

Correct answer: C

Rationale: Weight gain when consuming excess calories is not an example of a homeostatic mechanism. Homeostasis refers to the body's ability to maintain a stable internal environment despite external changes. The other options listed (A, B, and D) involve physiological responses aimed at restoring balance or stability within the body (e.g., regulating body temperature, blood pressure, and blood sugar levels). Shivering, increasing heart rate, and secreting insulin are mechanisms to counteract specific imbalances and maintain internal equilibrium. In contrast, weight gain due to excess calorie intake does not represent a specific regulatory mechanism but rather an outcome of energy imbalance. The body stores excess energy as fat rather than actively regulating a physiological parameter to restore balance.

2. Which of the following is NOT a part of a plant cell?

A. Cell wall
B. Plasma membrane
C. Vacuole
D. Mitochondria

Correct answer: D

Rationale: A) Cell wall: This is a structure found in plant cells that provides support and protection. B) Plasma membrane: Also known as the cell membrane, it surrounds the cell and regulates the passage of substances in and out of the cell. C) Vacuole: This is a storage organelle found in plant cells that stores water, nutrients, and waste products. D) Mitochondria: Mitochondria are membrane-bound organelles found in both plant and animal cells. They are responsible for producing energy in the form of ATP through cellular respiration. Therefore, the correct answer is D) Mitochondria, as it is a part of a plant cell.

3. What presents the correct order of cellular respiration?

A. Glycolysis, Acetyl-CoA, Citric Acid Cycle, Electron Transport Chain
B. Citric Acid Cycle, Glycolysis, Acetyl-CoA, Electron Transport Chain
C. Glycolysis, Acetyl-CoA, Electron Transport Chain, Citric Acid Cycle
D. Glycolysis, Citric Acid Cycle, Electron Transport Chain, Acetyl-CoA

Correct answer: A

Rationale: The correct order of cellular respiration is Glycolysis, Acetyl-CoA, Citric Acid Cycle, and Electron Transport Chain. Glycolysis initiates the breakdown of glucose in the cytoplasm, leading to the formation of pyruvate. This pyruvate is then converted to Acetyl-CoA in the mitochondria, which enters the Citric Acid Cycle to generate energy-rich molecules like NADH and FADH2. Finally, the Electron Transport Chain, located in the inner mitochondrial membrane, utilizes these energy carriers to produce ATP through oxidative phosphorylation. Choice B is incorrect because it starts with the Citric Acid Cycle, which comes after Glycolysis. Choice C is incorrect as it places the Citric Acid Cycle before the Electron Transport Chain. Choice D is incorrect by placing Acetyl-CoA last instead of before the Citric Acid Cycle.

4. Which brain area can lead to difficulty with language and speech if damaged?

A. Broca's area
B. Wernicke's area
C. Occipital lobe
D. Cerebellum

Correct answer: A

Rationale: Damage to Broca's area, located in the frontal lobe of the brain, can result in difficulties with language and speech production. Broca's area is responsible for speech production and coordinating the muscles involved in speech. Damage to this area can lead to Broca's aphasia, characterized by struggles in forming words and sentences. On the other hand, damage to Wernicke's area in the temporal lobe can cause issues with language comprehension and producing meaningful language, leading to Wernicke's aphasia. The occipital lobe primarily processes visual information, while the cerebellum is responsible for coordinating movement and balance, not language and speech.

5. What would be an appropriate control variable for this experiment?

A. The period
B. The length of the string
C. The mass of the ball
D. The color of the ball

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.