what type of immunity does a vaccine provide choose only one best answer

ATI TEAS 7

TEAS Practice Test Science

1. What type of immunity does a vaccine provide? Choose only ONE best answer.

A. Naturally acquired passive immunity
B. Artificially acquired passive immunity
C. Naturally acquired active immunity
D. Artificially acquired active immunity

Correct answer: D

Rationale: The correct answer is D: Artificially acquired active immunity. Vaccines work by stimulating the immune system to produce an active response, leading to the development of immunity against specific pathogens. Choice A, naturally acquired passive immunity, is incorrect as it refers to the temporary immunity passed from mother to child, not through vaccines. Choice B, artificially acquired passive immunity, is also incorrect because passive immunity involves the transfer of pre-formed antibodies, not the stimulation of the immune system by vaccines. Choice C, naturally acquired active immunity, is incorrect since it is acquired through natural exposure to pathogens, not through vaccines.

2. What is the balanced chemical equation for the reaction between sodium and chlorine to form sodium chloride?

A. Na + Cl2 -> NaCl
B. 2Na + Cl2 -> 2NaCl
C. Na2 + Cl -> 2NaCl
D. Na + 2Cl -> NaCl2

Correct answer: B

Rationale: In a balanced chemical equation, the number of atoms of each element must be the same on both sides of the equation. When sodium (Na) reacts with chlorine (Cl2) to form sodium chloride (NaCl), we need to ensure the equation is balanced. There are 2 chlorine atoms in Cl2; hence, we need 2 sodium atoms on the left side to balance it. Therefore, the balanced chemical equation is 2Na + Cl2 -> 2NaCl. Choice A is incorrect because it does not have the correct coefficients to balance the equation. Choice C is incorrect as it incorrectly represents the formula of sodium. Choice D is incorrect as it forms NaCl2, which is not the correct compound formed in this reaction.

3. Which structure in the skin is responsible for producing melanin?

A. Sudoriferous gland
B. Melanocyte
C. Sebaceous gland
D. Hair follicle

Correct answer: B

Rationale: The correct answer is B: Melanocyte. Melanocytes in the skin are responsible for producing melanin, the pigment that gives skin its color and provides protection against harmful UV radiation. Sudoriferous glands produce sweat, sebaceous glands produce sebum (oil), and hair follicles are associated with hair growth. However, the specific function of producing melanin is attributed to melanocytes, making them the correct answer in this context.

4. What is the control, if any, in this experiment?

A. There is no control in this experiment
B. The control is the water
C. The control is the diet soda
D. The control is the amount of sunlight provided to the plants

Correct answer: B

Rationale: The correct answer is B: 'The control is the water.' In a scientific experiment, the control group is used as a baseline comparison to evaluate the effects of the variables being tested. Here, the water serves as the control group against which the effects of other substances like diet soda or different amounts of sunlight can be compared. Choice A is incorrect as every experiment should have a control group for comparison. Choice C and D are incorrect as they are not the standard control in this scenario.

5. What happens to the density of a substance if its mass increases while its volume remains constant?

A. Density increases
B. Density decreases
C. Density remains constant
D. Density becomes zero

Correct answer: A

Rationale: When the mass of a substance increases while its volume remains constant, the density, which is calculated by dividing mass by volume, will increase. This is because with a higher mass and the volume staying the same, the ratio of mass to volume (density) will be greater, resulting in an overall increase in density. Choice B, 'Density decreases,' is incorrect because an increase in mass with constant volume leads to a higher density. Choice C, 'Density remains constant,' is incorrect as an increase in mass will cause the density to increase. Choice D, 'Density becomes zero,' is incorrect because even with an increase in mass, as long as volume remains constant, density will not reach zero; it will increase instead.