1. The human immunodeficiency virus (HIV) targets and destroys which type of immune cell?

A. Neutrophils
B. Macrophages
C. Helper T cells
D. Memory B cells

Correct answer: A

Rationale: The correct answer is C: Helper T cells. HIV targets and destroys Helper T cells, which are a crucial component of the immune system responsible for coordinating the immune response. Neutrophils and macrophages are also important immune cells, but they are not the primary target of HIV. Memory B cells are responsible for mounting a rapid response upon re-exposure to a pathogen but are not the main target of HIV. Thus, HIV primarily affects Helper T cells, leading to the weakening of the immune system and the development of acquired immunodeficiency syndrome (AIDS).

2. What is the main component of sweat?

A. Urea
B. Glucose
C. Water
D. Electrolytes

Correct answer: C

Rationale: Rationale: - Sweat is primarily composed of water, making up the majority of its content. Water helps regulate body temperature by evaporating from the skin's surface, which cools the body down. - While sweat does contain small amounts of other substances like urea, glucose, and electrolytes, water is the main component that is secreted by sweat glands to help regulate body temperature during physical activity or in response to heat.

3. Which skin condition is characterized by patches of inflamed, reddened skin and is often triggered by allergens or stress?

A. Eczema
B. Psoriasis
C. Acne
D. Vitiligo

Correct answer: A

Rationale: The correct answer is A: Eczema. Eczema is a skin condition characterized by patches of inflamed, reddened skin that can be triggered by allergens or stress. It is a chronic condition that can cause itching and discomfort. Psoriasis (option B) is a different skin condition characterized by red, scaly patches on the skin. Acne (option C) is a common skin condition characterized by pimples and clogged pores. Vitiligo (option D) is a condition where the skin loses its pigment, resulting in white patches. Therefore, eczema best fits the description provided in the question.

4. Which of these organisms belongs to the kingdom Protista?

A. Coral
B. Yeast
C. Euglena
D. Mushroom

Correct answer: C

Rationale: Rationale: A) Coral belongs to the kingdom Animalia, specifically in the phylum Cnidaria. B) Yeast belongs to the kingdom Fungi. C) Euglena is a unicellular organism that belongs to the kingdom Protista. It is a type of protist that has characteristics of both plants and animals. D) Mushroom belongs to the kingdom Fungi. Therefore, among the options provided, only Euglena belongs to the kingdom Protista.

5. Maintaining good muscle strength and flexibility as we age becomes important to avoid:

A. Headaches
B. Falls
C. Anxiety
D. Common cold

Correct answer: B

Rationale: The correct answer is B: 'Falls.' Maintaining good muscle strength and flexibility as we age is crucial for preventing falls, which become more common with age and can lead to serious injuries such as fractures. Strong muscles and good flexibility help in maintaining balance and stability, reducing the risk of falls. Headaches, anxiety, and the common cold are not directly related to muscle strength and flexibility, making them less likely to be avoided by focusing on these aspects of physical health.