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. Which compound is a component of baking soda and is important for maintaining pH balance in the body?

A. Potassium
B. Sodium
C. Calcium
D. Sodium bicarbonate

Correct answer: D

Rationale: The correct answer is D, Sodium bicarbonate. Sodium bicarbonate, commonly known as baking soda, is a compound that plays a crucial role in maintaining pH balance in the body. When ingested, sodium bicarbonate acts as a buffer, helping to regulate the body's pH levels. It is essential for various physiological functions. Choices A, B, and C are incorrect. Potassium, calcium, and sodium are important minerals in the body but are not components of baking soda or directly responsible for maintaining pH balance in the same way as sodium bicarbonate.

3. Which part of the brain is responsible for balance and coordination?

A. Cerebrum
B. Cerebellum
C. Medulla oblongata
D. Thalamus

Correct answer: B

Rationale: The correct answer is the cerebellum. The cerebellum is responsible for balance, coordination, and fine motor control. It integrates sensory information from the vestibular system in the inner ear and proprioceptive information from muscles and joints to coordinate voluntary movements. The cerebrum is primarily involved in higher brain functions like thinking and decision-making. The medulla oblongata controls vital autonomic functions such as breathing and heart rate. The thalamus serves as a relay station for sensory information before sending it to the cerebral cortex for further processing.

4. Which of the following lists the structures found beneath the rib in descending order?

A. Nerve → Artery → Vein
B. Vein → Nerve → Artery
C. Vein → Artery → Nerve
D. Artery → Nerve → Vein

Correct answer: C

Rationale: The correct order of structures found beneath the rib in descending order is Vein → Artery → Nerve. This sequence is important to remember for medical procedures like inserting a chest tube to ensure precision and avoid complications. Choice A is incorrect because the nerve is not typically the structure closest to the rib. Choice B is incorrect as the vein is usually closer to the rib than the nerve. Choice D is incorrect as the artery is usually closer to the rib than the nerve.

5. What is the independent variable in the botanist's experiment?

A. Temperature
B. Root tissue
C. Light exposure
D. Root length

Correct answer: A

Rationale: In an experiment, the independent variable is the factor that is deliberately manipulated or changed by the researcher. The botanist is likely altering the temperature to observe its effect on the plants. Therefore, temperature is the independent variable in the botanist's experiment. Choice B, root tissue, is not the independent variable as it is not the factor being intentionally changed in the experiment. Choice C, light exposure, and choice D, root length, are also not the independent variables as they are not the factors being purposely manipulated by the researcher in this scenario.