1. The hormone responsible for the "fight-or-flight" response in stressful situations is produced by the:

A. Thyroid gland
B. Pituitary gland
C. Adrenal gland
D. Pancreas

Correct answer: C

Rationale: The correct answer is C: Adrenal gland. The adrenal gland is responsible for producing the hormone known as adrenaline, which triggers the 'fight-or-flight' response in stressful situations. This response prepares the body to either confront the stressor or flee from it. The thyroid gland (A) is responsible for producing hormones that regulate metabolism, growth, and development. The pituitary gland (B) controls several other endocrine glands and produces a variety of hormones. The pancreas (D) is responsible for producing insulin and glucagon, which regulate blood sugar levels but are not directly involved in the 'fight-or-flight' response.

2. Which word completes the sentence: "Despite the storm, the concert ____ went on."

A. nevertheless
B. however
C. therefore
D. nonetheless

Correct answer: D

Rationale: "Nonetheless" emphasizes the continuation of the concert despite the contrary circumstance.

3. Which of the following is NOT a type of chemical bond?

A. Ionic bond
B. Covalent bond
C. Metallic bond
D. Gravitational bond

Correct answer: D

Rationale: Although gravity exists, it's not considered a chemical bond responsible for holding atoms together within molecules.

4. The Merkel cells, located in the epidermis, are specialized for:

A. Melanin production
B. Temperature sensation
C. Touch perception
D. Immune defense

Correct answer: C

Rationale: The correct answer is C: 'Touch perception.' Merkel cells, also known as Merkel discs, are found in the skin's epidermal layer and are responsible for sensing touch. These cells are located near nerve endings and help detect light touch and pressure on the skin. They play a crucial role in the perception of tactile sensations and are not involved in melanin production, temperature sensation, or immune defense. Therefore, the specialized function of Merkel cells is primarily related to touch perception, making option C the correct choice.

5. When light reflects from a surface, what determines the angle of reflection?

A. The material of the surface
B. The wavelength of the light
C. The angle of incidence
D. The intensity of the light

Correct answer: C

Rationale: The angle of reflection is always equal to the angle of incidence according to the law of reflection, regardless of the material, wavelength, or intensity.