which structure controls the hormones secreted by the pituitary gland

ATI TEAS 7

ATI TEAS 7 Science Practice Test

1. Which structure controls the hormones secreted by the pituitary gland?

A. Hypothalamus
B. Adrenal gland
C. Testes
D. Pancreas

Correct answer: A

Rationale: The correct answer is A: Hypothalamus. The hypothalamus controls the release of hormones from the pituitary gland. It acts as a master regulator of the endocrine system by producing releasing and inhibiting hormones that influence the secretion of hormones from the pituitary gland. Choice B, the Adrenal gland, is incorrect because while it plays a role in hormone production, it is not responsible for controlling the pituitary gland's hormones. Choice C, the Testes, and Choice D, the Pancreas, are also incorrect as they are not directly involved in controlling the hormones secreted by the pituitary gland.

2. Which of the following statements about the autonomic nervous system (ANS) is true?

A. It controls involuntary functions
B. It contains motor (efferent) neurons
C. It contains sensory (afferent) neurons
D. It contains both parasympathetic and sympathetic nerves

Correct answer: D

Rationale: The correct answer is D because the autonomic nervous system (ANS) is responsible for controlling involuntary functions and contains both parasympathetic and sympathetic nerves. Choices A and B are incorrect as they do not fully capture the role of the ANS. While the ANS does control involuntary functions, this is a broader concept than just the reflex arc. While the ANS does contain motor (efferent) neurons, it also includes sensory (afferent) neurons, which are not specifically mentioned in the question. Therefore, choice C is not fully accurate. Choice D provides the most accurate and comprehensive description of the autonomic nervous system by highlighting its components, the parasympathetic and sympathetic nerves, which work together to regulate various bodily functions.

3. What is a mutation?

A. A change in the DNA sequence
B. A type of protein
C. A normal part of the DNA replication process
D. A harmless variation in DNA

Correct answer: A

Rationale: A mutation is defined as a change in the DNA sequence, which can occur due to various factors such as errors during DNA replication, exposure to mutagens (e.g., chemicals, radiation), or spontaneous changes. These alterations can lead to modifications in the genetic information carried by an organism, resulting in effects that can range from harmless variations to causing genetic disorders or diseases. Mutations play a crucial role in genetic diversity and evolution. Choices B, C, and D are incorrect as they do not accurately define what a mutation is. Option B is incorrect because mutations are not a type of protein but rather changes in DNA. Option C is incorrect because while mutations can occur during DNA replication, they are not considered a 'normal' part of the process as they can lead to genetic variations. Option D is incorrect because mutations can have a wide range of effects and are not always harmless variations.

4. How do organisms maintain homeostasis?

A. By increasing their body temperature, blood pH, and fluid balance.
B. By undergoing biochemical processes and absorbing energy to increase entropy.
C. By undergoing biochemical processes to maintain the order of their external environment.
D. By using free energy and matter via biochemical processes to work against entropy.

Correct answer: D

Rationale: Organisms maintain homeostasis by utilizing free energy and matter through biochemical processes to counteract entropy, which helps in preserving internal stability. This process involves maintaining a balance within the organism's internal environment despite external changes, ensuring proper functioning and survival. Choice A is incorrect because increasing body temperature, blood pH, and fluid balance alone do not define the comprehensive process of maintaining homeostasis. Choice B is incorrect as absorbing energy to increase entropy goes against the concept of maintaining internal stability. Choice C is incorrect as maintaining the order of the external environment does not directly contribute to the organism's internal stability and balance.

5. Which of the following constituents of blood is a biconcave disc that is round and flat without a nucleus?

A. Plasma
B. Platelet
C. RBC
D. WBC

Correct answer: C

Rationale: The correct answer is C, RBC (Red Blood Cell). Red blood cells are biconcave discs that lack a nucleus, allowing them to carry oxygen efficiently. Plasma (A) is the liquid component of blood that carries various substances. Platelets (B) are cell fragments important for blood clotting. White blood cells (WBCs) (D) are part of the immune system and have a nucleus.