1. What is the main consequence of a malfunctioning thyroid gland that produces abnormally low levels of thyroid hormones?

A. Increased energy levels and weight loss
B. Decreased heart rate and body temperature
C. Enhanced muscle growth and bone development
D. Faster metabolism and heightened alertness

Correct answer: B

Rationale: The correct answer is B: 'Decreased heart rate and body temperature.' When the thyroid gland produces abnormally low levels of thyroid hormones (hypothyroidism), it can lead to a decrease in metabolic rate, resulting in symptoms such as fatigue, weight gain, and feeling cold. A lower metabolic rate can slow down heart rate and decrease body temperature. The other options (A, C, D) are not characteristic of hypothyroidism. Increased energy levels and weight loss, enhanced muscle growth and bone development, and faster metabolism and heightened alertness are more commonly associated with hyperthyroidism, where the thyroid gland produces excess hormones.

2. What is the main function of dietary fiber in the digestive system?

A. To provide energy
B. To break down fats
C. To promote gut bacteria growth
D. To aid in absorption of nutrients

Correct answer: C

Rationale: Rationale: Dietary fiber refers to the indigestible portion of plant foods that passes relatively intact through the digestive system. While fiber does not provide energy directly to the body, it plays a crucial role in promoting the growth of beneficial gut bacteria. These bacteria help in the fermentation of fiber, producing short-chain fatty acids that can be used as an energy source by the body. Additionally, fiber helps regulate bowel movements, maintain gut health, and support overall digestive function. Therefore, the main function of dietary fiber in the digestive system is to promote gut bacteria growth.

3. What is the term for a genetic disorder caused by a mutation in a mitochondrial gene?

A. Autosomal dominant disorder
B. Autosomal recessive disorder
C. Sex-linked disorder
D. Mitochondrial disorder

Correct answer: D

Rationale: Rationale: A) Autosomal dominant disorder: This type of genetic disorder is caused by a mutation in one copy of an autosomal gene. It is not related to mitochondrial gene mutations. B) Autosomal recessive disorder: This type of genetic disorder is caused by mutations in both copies of an autosomal gene. It is not related to mitochondrial gene mutations. C) Sex-linked disorder: This type of genetic disorder is caused by mutations in genes located on the sex chromosomes (X or Y). It is not related to mitochondrial gene mutations. D) Mitochondrial disorder: Mitochondrial disorders are genetic disorders caused by mutations in genes located in the mitochondria, the energy-producing structures within cells. These disorders are inherited maternally and can affect various organs and systems in the body due to the role of mitochondria in energy production.

4. What is the SI unit of measurement for acceleration?

A. Meters per second (m/s)
B. Newton (N)
C. Meters (m)
D. Meters per second squared (m/sÃ‚Â²)

Correct answer: d

Rationale: Acceleration is measured in meters per second squared (m/sÃ‚Â²) in the SI unit system.

5. Which of the following is NOT a characteristic of a chemical reaction?

A. Formation of new substances
B. Release or absorption of energy
C. Change in color
D. Change in temperature

Correct answer: C

Rationale: While color change can be an indicator of a chemical reaction, it's not always present, and some reactions occur without a visible color change.

6. What is the end result of mitosis in animal cells?

A. The production of two identical daughter cells
B. The production of four haploid cells
C. The production of a single diploid cell
D. The production of a single haploid cell

Correct answer: A

Rationale: Rationale: Mitosis is a type of cell division that results in the production of two identical daughter cells, each having the same number of chromosomes as the parent cell. This process is essential for growth, repair, and maintenance of multicellular organisms. During mitosis, the replicated chromosomes are separated into two nuclei, and the cell then divides to form two genetically identical daughter cells. Options B, C, and D are incorrect because mitosis does not result in the production of four haploid cells, a single diploid cell, or a single haploid cell.