a substance that can donate a hydroxide ion oh in solution is classified as a

ATI TEAS 7

TEAS Test 7 science

1. Which of the following substances can donate a hydroxide ion (OH-) in solution?

A. Salt
B. Base
C. Neutral compound
D. Dehydrating agent

Correct answer: B

Rationale: The correct answer is B: Base. A base is a substance that can donate hydroxide ions (OH-) in solution. Bases increase the concentration of hydroxide ions by either accepting protons (H+) or donating hydroxide ions. Salts are ionic compounds made of cations and anions, which do not directly donate hydroxide ions. Neutral compounds do not significantly affect the concentration of hydroxide ions. Dehydrating agents are substances that remove water molecules from other compounds, unrelated to donating hydroxide ions.

2. In ecology, what defines a closed system?

A. Exchanges energy but not matter
B. Exchanges both energy and matter
C. Exchanges neither energy nor matter
D. Recycles nutrients efficiently

Correct answer: A

Rationale: In ecology, a closed system is one that does not exchange matter with its surroundings but can exchange energy. This means that while energy can enter or leave the system, the amount of matter within the system remains constant. Option A correctly defines a closed system in ecology. Choices B and C are incorrect as a closed system does not exchange matter or energy. Option D is unrelated to the concept of a closed system in ecology.

3. Microfilaments and microtubules are both components of the cytoskeleton, but they have different functions. Which of these describes microfilaments?

A. Provide structural support and shape
B. Facilitate cell movement and contraction
C. Form the mitotic spindle during cell division
D. Transport materials within the cell

Correct answer: A

Rationale: Microfilaments are thin, solid rods made of the protein actin and are primarily responsible for providing structural support to the cell and determining its shape. While they also play a role in cell movement, their main function is related to maintaining the structural integrity of the cell. Choice B, 'Facilitate cell movement and contraction,' describes microtubules, which are responsible for facilitating cell movement, providing structural support, and aiding in cell division. Choice C, 'Form the mitotic spindle during cell division,' specifically refers to the function of microtubules in forming the mitotic spindle. Choice D, 'Transport materials within the cell,' is characteristic of microtubules that are involved in intracellular transport of organelles and materials within the cell.

4. Which of the following is NOT a major function of the respiratory system in humans?

A. It provides a large surface area for gas exchange of oxygen and carbon dioxide.
B. It helps regulate the blood's pH.
C. It helps cushion the heart against jarring motions.
D. It is responsible for vocalization.

Correct answer: C

Rationale: Option C, 'It helps cushion the heart against jarring motions,' is NOT a major function of the respiratory system in humans. The primary functions of the respiratory system include gas exchange, regulation of blood pH, and vocalization. The respiratory system does not play a role in cushioning the heart; that function is primarily carried out by the pericardium and other protective structures around the heart. Choices A, B, and D are major functions of the respiratory system in humans. Choice A refers to the respiratory system's role in gas exchange, Choice B highlights its involvement in regulating blood pH, and Choice D points out its responsibility for vocalization.

5. Which of the following hormones would cause skin color to become darker?

A. Follicle-stimulating
B. Growth-stimulating
C. Thyroid-stimulating
D. Melanocyte-stimulating

Correct answer: D

Rationale: The correct answer is D, Melanocyte-stimulating. Melanocyte-stimulating hormone (MSH) stimulates melanocytes in the skin to produce more melanin, leading to darker skin pigmentation. Choices A, B, and C are incorrect as Follicle-stimulating hormone (FSH) stimulates follicle growth in the reproductive system, Growth-stimulating hormone is a vague term not specific to any known hormone, and Thyroid-stimulating hormone (TSH) stimulates the thyroid gland to produce thyroid hormones, not affecting skin color pigmentation.