homeostasis is the

ATI RN

ATI Anatomy and Physiology Online Practice

1. What is homeostasis?

A. The inability to keep body weight within normal limits.
B. Room temperature decreasing because a window is open.
C. Ingestion of more food than needed.
D. The tendency of the body to maintain a stable internal environment.

Correct answer: D

Rationale: The correct answer is D: Homeostasis refers to the body's ability to maintain a stable internal environment despite external changes. Choices A, B, and C are incorrect. Choice A describes obesity, choice B describes a specific scenario with room temperature, and choice C refers to overeating, which is not related to homeostasis.

2. Which of the following substances is involved in the destruction of ingested pathogens?

A. lymphatic fluid
B. stomach acid
C. bicarbonate
D. lipase

Correct answer: B

Rationale: The correct answer is stomach acid. Stomach acid, also known as gastric acid, plays a crucial role in destroying ingested pathogens due to its high acidity. The low pH of stomach acid helps to kill bacteria and other pathogens that may be present in the food we consume. Lymphatic fluid is involved in immune function and fat absorption, not pathogen destruction. Bicarbonate is a base that neutralizes stomach acid to prevent damage to the stomach lining. Lipase is an enzyme that aids in the digestion of fats but is not involved in pathogen destruction.

3. Metabolism is defined as _____.

A. the removal of wastes produced by chemical reactions
B. the breakdown of substances into simpler forms
C. the taking in of nutrients
D. all the chemical reactions occurring in an organism that support life

Correct answer: D

Rationale: Metabolism refers to all the chemical reactions that take place within an organism to sustain life, including processes such as breaking down molecules, building new molecules, and energy production. Choice A is incorrect because it describes excretion rather than metabolism. Choice B is incorrect as it specifically refers to the breakdown of substances, not encompassing the entirety of metabolic processes. Choice C is incorrect as it focuses solely on nutrient intake, which is just one aspect of metabolism.

4. Temperature is a form of energy, whereas heat is a measurement of the intensity of the temperature.

A. TRUE
B. FALSE
C. Not Sure
D. None of the above

Correct answer: A

Rationale: The statement is true. Temperature is a measure of the average kinetic energy of the particles in a substance, while heat is the transfer of energy from a hotter object to a colder one. Heat is not a measurement of the intensity of temperature, but rather the energy transfer due to a temperature difference. Therefore, the correct answer is True. Choice B (False) is incorrect as the statement is true based on the definitions of temperature and heat.

5. What causes wrinkled and sagging skin?

A. Drinking too much water
B. Heredity alone
C. Loss of subcutaneous fat and reduced levels of elastin and collagen
D. Excess subcutaneous fat

Correct answer: C

Rationale: Wrinkled and sagging skin is primarily caused by the loss of subcutaneous fat and reduced levels of elastin and collagen in the skin. Choice A is incorrect as drinking too much water does not lead to wrinkled and sagging skin. Choice B is incorrect because heredity alone does not cause this condition. Excess subcutaneous fat, as mentioned in Choice D, can contribute to a different skin appearance, such as puffiness, but not wrinkled and sagging skin.