1. Bone is a type of

A. Epithelial tissue
B. Connective tissue
C. Hard connective tissue
D. Muscle tissue

Correct answer: C

Rationale: The correct answer is C: "Hard connective tissue." Bone is classified as hard connective tissue because it is composed of cells embedded in a matrix of mineralized collagen fibers, providing support and protection to the body. Epithelial tissue (A) covers body surfaces and lines cavities, while connective tissue (B) includes bone, cartilage, and blood. Muscle tissue (D) is responsible for movement and is not the same as bone tissue.

2. Which of the following is an example of an aromatic hydrocarbon?

A. Ethane
B. Benzene
C. Propane
D. Butene

Correct answer: B

Rationale: Benzene is an example of an aromatic hydrocarbon. The other choices are aliphatic hydrocarbons.

3. Which gland located in the neck is responsible for regulating metabolism, growth, and development?

A. Parathyroid gland
B. Thyroid gland
C. Pituitary gland
D. Thymus gland

Correct answer: B

Rationale: The correct answer is B: Thyroid gland. The thyroid gland is located in the neck and plays a crucial role in regulating metabolism, growth, and development. It produces hormones such as thyroxine (T4) and triiodothyronine (T3) that control the body's metabolic rate, affecting energy levels and growth. The parathyroid gland (A) regulates calcium levels in the body, the pituitary gland (C) controls several other glands and their hormone production, and the thymus gland (D) is involved in the immune system's development. Therefore, the thyroid gland is the most appropriate choice for the functions described in the question.

4. What is the primary function of hair on the human body?

A. Insulation
B. Sensory perception
C. Protection
D. Vitamin D synthesis

Correct answer: A

Rationale: The primary function of hair on the human body is insulation. Hair acts as a protective layer to help regulate body temperature by trapping heat close to the skin. This insulation property is especially important in colder climates to prevent excessive heat loss from the body. While hair can also provide some level of protection from external elements and minor injuries, its main role is to insulate the body. Sensory perception is mainly attributed to nerve endings in the skin rather than hair. Vitamin D synthesis is primarily dependent on exposure to sunlight rather than hair. Therefore, option A, insulation, is the correct answer.

5. What is the name for the mixture of reactants and products present during a chemical reaction?

A. Solution
B. Mixture
C. Reaction mixture
D. Precipitate

Correct answer: C

Rationale: This mixture contains both the starting materials (reactants) and the newly formed substances (products) during the reaction process.

6. A person who carries a pathogen but does not exhibit any symptoms is considered:

A. Asymptomatic carrier
B. Opportunistic pathogen
C. Nosocomial infection
D. Vector-borne disease

Correct answer: A

Rationale: Rationale: An asymptomatic carrier is a person who carries a pathogen (such as a virus or bacterium) but does not show any symptoms of the infection themselves. Despite not exhibiting symptoms, asymptomatic carriers can still spread the pathogen to others, potentially causing illness in those who come into contact with them. This term specifically refers to individuals who are infected but do not develop symptoms, distinguishing them from symptomatic carriers who do show signs of the infection. Option A is the most appropriate choice in this context as it accurately describes a person who carries a pathogen without displaying symptoms. B) Opportunistic pathogen: This term refers to pathogens that typically do not cause disease in healthy individuals but can become pathogenic in individuals with weakened immune systems. C) Nosocomial infection: This term refers to infections that are acquired in a hospital or healthcare facility. D) Vector-borne disease: This term refers to diseases