how do organisms maintain homeostasis

ATI TEAS 7

ATI TEAS Science

1. 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.

2. What is the name of the white blood cells that attack foreign invaders?

A. Phagocytes
B. Lymphocytes
C. Platelets
D. Red blood cells

Correct answer: A

Rationale: Phagocytes are a type of white blood cell that plays a crucial role in the immune system by engulfing and digesting foreign invaders such as bacteria, viruses, and other harmful substances. They are part of the body's innate immune response and are essential for protecting the body against infections. Lymphocytes, on the other hand, are another type of white blood cell involved in the adaptive immune response, producing antibodies, and coordinating immune responses. Platelets are cell fragments involved in blood clotting, while red blood cells are responsible for carrying oxygen to tissues. Therefore, the correct answer is Phagocytes (Choice A) because they are specifically tasked with attacking and destroying foreign invaders in the body, distinguishing them from the other choices which have different functions within the immune system.

3. Which of the following best describes a group of cells working together?

A. Organelle
B. Tissue
C. Organ
D. Organ system

Correct answer: B

Rationale: The correct answer is B: Tissue. Tissue is a group of cells that work together to perform a specific function. Organelle refers to specialized structures within a cell, organ is a structure made up of different types of tissues working together, and organ system is a group of organs working together to perform complex functions. Therefore, tissue is the most appropriate term to describe a group of cells working together.

4. Which of the following glands produces hormones that regulate metabolism?

A. Adrenal gland
B. Pituitary gland
C. Thyroid gland
D. Liver

Correct answer: C

Rationale: The thyroid gland is responsible for producing hormones that play a crucial role in regulating metabolism. One of the key hormones produced by the thyroid gland is thyroxine, which directly influences the body's metabolic rate. Therefore, the correct answer is the thyroid gland. The adrenal gland produces hormones like adrenaline, which are associated with the stress response and not primarily metabolic regulation. The pituitary gland regulates various other hormones but is not primarily responsible for metabolic regulation. The liver has a role in metabolism, mainly in processes like detoxification and nutrient storage, but it is not a gland that primarily produces hormones for metabolic regulation, making it an incorrect choice in this context.

5. Which of the following statements regarding the pericardium is not correct?

A. It allows for the heart to work in a relatively friction-free environment
B. It is a single-walled layer around the heart
C. It prevents overfilling of the heart with blood
D. It protects and anchors the heart

Correct answer: B

Rationale: The correct statement about the pericardium is that it is double-walled, not single-walled. Choice A is correct because the pericardium does allow the heart to work in a relatively friction-free environment, reducing friction during heartbeats. Choice C is correct as the pericardium helps prevent the overfilling of the heart with blood. Choice D is also correct as the pericardium serves to protect and anchor the heart in place within the chest cavity.