1. The adaptive immune system has two main branches: humoral and cell-mediated immunity. Which type of immune cell is primarily responsible for antibody production?

A. Helper T cells
B. Cytotoxic T cells
C. B cells
D. Natural killer cells

Correct answer: C

Rationale: The correct answer is C: B cells. B cells are a type of lymphocyte that plays a central role in humoral immunity by producing antibodies. When activated by antigens, B cells differentiate into plasma cells, which are responsible for producing and secreting antibodies. Helper T cells (option A) primarily assist in activating B cells and other immune cells. Cytotoxic T cells (option B) are involved in cell-mediated immunity, where they directly kill infected cells. Natural killer cells (option D) are part of the innate immune system and target virus-infected and cancerous cells. Therefore, B cells are the immune cells primarily responsible for antibody production in the adaptive immune system.

2. What is the acceleration due to gravity near the Earth's surface?

A. 9.8 meters per second squared (m/sÂ²)
B. 6.3 meters per second squared (m/sÂ²)
C. 5.0 meters per second squared (m/sÂ²)
D. 12.5 meters per second squared (m/sÂ²)

Correct answer: a

Rationale: The acceleration due to gravity near the Earth's surface is approximately 9.8 m/sÂ²

3. What is the primary factor that determines whether a solute will dissolve in a solvent?

A. Temperature
B. Pressure
C. Molecular structure
D. Particle size

Correct answer: c

Rationale: The molecular structure of the solute and solvent plays a key role in determining solubility. The other choices may influence solubility but are not the primary determining factor.

4. An Egyptian model pyramid has a square base side length of 10cm and a height of 8cm. What is its volume?

A. 20 cu cm
B. 40 cu cm
C. 80 cu cm
D. 160 cu cm

Correct answer: D

Rationale: Use the formula for volume of a pyramid: (1/3) * base area * height. Calculate the base area (10cm * 10cm = 100 sq cm) and substitute: (1/3) * 100 sq cm * 8cm = 80 cu cm.

5. What is the scientific term for a broken bone?

A. Osteoporosis
B. Fracture
C. Sprain
D. Dislocation

Correct answer: B

Rationale: The correct answer is B: 'Fracture.' A fracture is the scientific term used to describe a broken bone. Osteoporosis (A) is a condition where bones become weak and brittle, increasing the risk of fractures. A sprain (C) is an injury to a ligament, not a bone. A dislocation (D) occurs when the bones in a joint are forced out of their normal position, but it is not the term for a broken bone.