1. Sunscreen protects the skin from harmful ultraviolet (UV) rays by

A. Reflecting UV rays away from the skin
B. Absorbing UV rays and converting them to heat
C. Blocking UV rays completely
D. Stimulating melanin production

Correct answer: B

Rationale: The correct answer is B: Absorbing UV rays and converting them to heat. Sunscreen contains ingredients that act as filters to absorb UV radiation before it reaches the skin. These filters then convert the UV rays into a less harmful form of energy, usually heat, which is then released from the body. This process helps prevent UV radiation from damaging the skin cells and causing sunburn or long-term skin damage. Reflecting UV rays away from the skin (A) and blocking UV rays completely (C) are not accurate functions of sunscreen. Additionally, stimulating melanin production (D) is not a direct way in which sunscreen protects the skin from UV rays.

2. Which sentence uses strong verbs to create a more vivid image?

A. The car moved slowly down the street.
B. The car drove sluggishly down the road.
C. The car inched down the avenue.
D. The car traveled down the thoroughfare.

Correct answer: C

Rationale: "Inched" creates a stronger image of the car's slow movement compared to "moved" or "drove."

3. What property of a substance remains constant regardless of changes in gravity?

A. Mass
B. Weight
C. Volume
D. Density

Correct answer: A

Rationale: Mass is a measure of the amount of matter in an object and remains constant regardless of changes in gravity. Weight, on the other hand, is a measure of the gravitational force acting on an object and varies with changes in gravity. Volume is the amount of space occupied by an object and can change with changes in gravity. Density is the mass of a substance per unit volume and can also change with changes in gravity if the volume changes.

4. Define the term "momentum" in physics.

A. Force exerted on an object
B. Speed of an object in motion
C. Mass in motion
D. Distance traveled per unit time

Correct answer: c

Rationale: Momentum is the product of an object's mass and velocity, describing its motion and resistance to changes in motion.

5. Identify the noun in the following sentence: The aroma of freshly baked bread filled the kitchen.

A. filled
B. kitchen
C. aroma
D. freshly

Correct answer: C

Rationale: Nouns name people, places, things, or ideas. "Aroma" names a specific type of smell.

6. The innate immune system provides:

A. Nonspecific, immediate defense against pathogens
B. Specific, long-term immune response through memory cells
C. Both (a) and (b)
D. Neither (a) nor (b)

Correct answer: A

Rationale: The correct answer is A: 'Nonspecific, immediate defense against pathogens.' The innate immune system is the body's first line of defense against pathogens and provides a rapid, nonspecific response. It includes physical barriers like the skin, chemical barriers like stomach acid, and cellular responses like inflammation. This system does not involve memory cells or provide long-term immunity, which are characteristics of the adaptive immune system. Therefore, option A accurately describes the function of the innate immune system as a quick and nonspecific defense mechanism.