1. The "master gland" of the endocrine system, located at the base of the brain, secretes various hormones that control other glands is the:

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

Correct answer: B

Rationale: The correct answer is B: Pituitary gland. The pituitary gland is often referred to as the "master gland" because it plays a crucial role in regulating other endocrine glands in the body. It is located at the base of the brain and secretes various hormones that control functions such as growth, metabolism, reproduction, and stress response. The thyroid gland (A) regulates metabolism, the adrenal gland (C) produces hormones involved in stress response, and the pancreas (D) is primarily responsible for regulating blood sugar levels through insulin production, but they do not serve as the master gland of the endocrine system.

2. Which structure helps regulate body temperature by constricting or dilating in response to temperature changes?

A. Sebaceous glands
B. Hair follicles
C. Sweat glands
D. Langerhans cells

Correct answer: C

Rationale: The correct answer is C: Sweat glands. Sweat glands play a crucial role in regulating body temperature by producing sweat that evaporates from the skin surface, cooling the body when it's hot. Sweat glands can constrict to reduce sweating in cooler temperatures and dilate to increase sweating when the body needs to cool down. Sebaceous glands are responsible for producing oil to lubricate the skin and hair follicles help in hair growth. Langerhans cells are immune cells in the skin. Therefore, sweat glands are the structure specifically involved in regulating body temperature through constriction and dilation in response to temperature changes.

3. Which word best describes the relationship between population growth and smart cities in the passage?

A. Cause and effect
B. Analogy
C. Contrast
D. Similarity

Correct answer: A

Rationale: The passage identifies rapid population growth as a challenge that smart cities are proposed to address, establishing a causal connection.

4. Which of the following is a pair of nerves that originates from the brain?

A. Spinal nerves
B. Olfactory nerves
C. Sciatic nerve
D. Optic nerve

Correct answer: B

Rationale: The correct answer is B, Olfactory nerves, because they are a pair of cranial nerves that originate from the brain and are responsible for the sense of smell. Spinal nerves (option A) originate from the spinal cord, not the brain. The sciatic nerve (option C) is a large nerve that runs from the lower back down the back of each leg and also originates from the spinal cord, not the brain. The optic nerve (option D) is a cranial nerve that connects the eye to the brain, but it is not a pair of nerves that originates from the brain. Therefore, the olfactory nerves are the only pair of nerves listed that specifically originate from the brain.

5. A concave mirror can be used to:

A. Focus light to a single point
B. Only create virtual images
C. Always magnify objects
D. Scatter light

Correct answer: A

Rationale: A concave mirror can be used to focus light to a single point because of its reflective surface that curves inward. When light rays parallel to the mirror's principal axis strike the mirror, they converge at a focal point, creating a real image. This property makes concave mirrors useful in applications like reflecting telescopes and headlights, where focusing light to a point is necessary for proper functioning. Virtual images are also created by concave mirrors, but the primary function is to focus light rather than create virtual images. Magnification of objects and scattering of light are not inherent properties of concave mirrors.

6. What is the waste product of protein digestion?

A. Glucose
B. Amino acids
C. Fatty acids
D. Ammonia

Correct answer: D

Rationale: Rationale: Protein digestion involves breaking down proteins into their constituent amino acids. During this process, the waste product produced is ammonia. Ammonia is a toxic compound that needs to be converted into urea in the liver and then excreted by the kidneys in the form of urine. Glucose is a product of carbohydrate digestion, amino acids are the building blocks of proteins, and fatty acids are the end products of fat digestion.