1. What is the difference between type 1 and type 2 diabetes, both related to insulin and blood sugar?

A. Type 1 is caused by insulin resistance, type 2 by insulin deficiency.
B. Type 1 is temporary, type 2 is permanent.
C. Type 1 affects adults, type 2 affects children
D. Type 1 is treated with diet only, type 2 requires medication.

Correct answer: A

Rationale: The correct answer is A: 'Type 1 is caused by insulin resistance, type 2 by insulin deficiency.' Type 1 diabetes is an autoimmune condition where the body attacks insulin-producing cells, leading to insulin deficiency. In contrast, type 2 diabetes occurs when the body becomes resistant to insulin's effects. This distinction is crucial for understanding the underlying causes and treatment approaches for each type of diabetes. Type 1 diabetes is not temporary; it is a chronic condition that requires lifelong management. Type 2 diabetes can also affect adults, but it is more commonly diagnosed in middle-aged and older adults. Treatment for type 1 diabetes typically involves insulin therapy along with diet and exercise, while type 2 diabetes may require medication in addition to lifestyle modifications.

2. What is the main function of the epiglottis?

A. To store bile
B. To absorb nutrients
C. To prevent food from entering the trachea
D. To produce digestive enzymes

Correct answer: C

Rationale: Rationale: The epiglottis is a flap of cartilage located at the base of the tongue that covers the opening of the trachea during swallowing to prevent food and liquids from entering the airway. This action helps direct food and liquids into the esophagus, which leads to the stomach for digestion, while also protecting the respiratory system from potential blockages that could lead to choking or aspiration pneumonia. Options A, B, and D are incorrect as the epiglottis is not involved in storing bile, absorbing nutrients, or producing digestive enzymes.

3. Half-life refers to the characteristic time it takes for:

A. Radioactive intensity to completely disappear
B. The number of neutrons in a nucleus to double
C. The number of protons in a nucleus to change
D. An isotope to decay by half of its initial quantity

Correct answer: D

Rationale: The correct answer is D: An isotope to decay by half of its initial quantity. The half-life of a substance is the time it takes for half of the initial quantity of radioactive atoms to decay. This is a characteristic property of each radioactive isotope and is used to determine the rate of decay of a substance. Option A is incorrect because radioactive intensity does not completely disappear in half-life, it only decreases by half. Options B and C are unrelated to the concept of half-life and do not accurately describe its definition.

4. What happens during a physical change in matter?

A. A new substance with different properties is formed
B. The chemical composition of the substance changes
C. The original substance can be recovered by physical means
D. Energy is either released or absorbed

Correct answer: C

Rationale: During a physical change in matter, the original substance undergoes a change in its physical state or appearance without any change in its chemical composition. This means that the original substance can be recovered by physical means, such as melting, freezing, boiling, or condensing. No new substance is formed (option A), the chemical composition remains the same (option B), and energy changes can occur but are not a defining characteristic of a physical change (option D).

5. The dark, round structures observed within some bacterial cells are most likely:

A. Ribosomes
B. Flagella
C. Endospores
D. Capsules

Correct answer: C

Rationale: Rationale: - Ribosomes are not dark, round structures within bacterial cells. Ribosomes are small, non-membranous organelles responsible for protein synthesis in all cells. - Flagella are not dark, round structures within bacterial cells. Flagella are long, whip-like appendages that some bacteria use for movement. - Capsules are not dark, round structures within bacterial cells. Capsules are outer layers of polysaccharides that some bacteria produce for protection and adherence. - Endospores are dark, round structures observed within some bacterial cells. Endospores are dormant, highly resistant structures formed by certain bacteria in response to harsh environmental conditions.