1. What is the purpose of the periosteum, the tough outer layer of bone?

A. Produces red blood cells
B. Provides protection and nourishment to bone
C. Forms the joint surface
D. Stores minerals

Correct answer: B

Rationale: The correct answer is B: 'Provides protection and nourishment to bone.' The periosteum is a tough outer layer of bone that serves multiple functions. It provides protection by acting as a barrier against infections and injuries. Additionally, the periosteum contains blood vessels that supply nutrients to the bone cells, aiding in bone growth, repair, and maintenance. While red blood cells are produced in the bone marrow, not in the periosteum, the periosteum's primary role is to support the overall health and integrity of the bone structure.

2. What is the phenomenon responsible for the mirage effect seen in deserts?

A. Diffraction
B. Refraction
C. Interference
D. Polarization

Correct answer: B

Rationale: Mirages occur due to the refraction of light by layers of air with different temperatures and densities, bending the light rays and creating the illusion of water on the horizon.

3. Which word best completes the sentence: "The scientist's breakthrough was met with _____ applause."

A. thunderous
B. scattered
C. polite
D. hesitant

Correct answer: A

Rationale: "Thunderous" emphasizes the intensity and volume of the applause, fitting the significance of the breakthrough.

4. "Ironic" and "serious" are:

A. synonyms (have the same meaning)
B. antonyms (have opposite meanings)
C. homonyms (sound the same but have different meanings)
D. none of the above

Correct answer: B

Rationale: "Ironic" means the opposite of "serious."

5. The element responsible for the yellow color of bananas is:

A. Potassium
B. Calcium
C. Phosphorus
D. Carotene

Correct answer: D

Rationale: Carotene is a type of carotenoid pigment found in fruits and vegetables, contributing to their yellow, orange, and red hues.

6. Which of the following is NOT a function of the integumentary system?

A. Regulation of body temperature
B. Protection from pathogens
C. Synthesis of vitamin D
D. Production of digestive enzymes

Correct answer: D

Rationale: The correct answer is D: "Production of digestive enzymes." The integumentary system primarily consists of the skin, hair, nails, and glands. Its main functions include regulating body temperature through processes like sweating and shivering, protecting the body from pathogens and external threats, and synthesizing vitamin D when exposed to sunlight. However, the production of digestive enzymes is not a function of the integumentary system. Digestive enzymes are primarily produced by organs such as the pancreas and salivary glands to aid in the breakdown of food in the digestive system, which is separate from the functions of the integumentary system.