1. Which type of white blood cell directly attacks and destroys pathogens like bacteria and viruses?

A. Neutrophils
B. Lymphocytes
C. Monocytes
D. Eosinophils

Correct answer: A

Rationale: The correct answer is A: Neutrophils. Neutrophils are a type of white blood cell that plays a crucial role in the innate immune response by directly attacking and destroying pathogens like bacteria and viruses. They are the most abundant type of white blood cell and are known for their rapid response to infections. Neutrophils work by engulfing and digesting pathogens through a process called phagocytosis. Lymphocytes (option B) are involved in adaptive immunity, producing antibodies and coordinating immune responses. Monocytes (option C) differentiate into macrophages and dendritic cells, playing a role in phagocytosis and antigen presentation. Eosinophils (option D) are primarily involved in combating parasitic infections and allergic reactions, not directly attacking bacteria and viruses.

2. What is the function of arrector pili muscles?

A. To control sweat production
B. To contract and cause goosebumps
C. To produce sebum
D. To sense touch

Correct answer: B

Rationale: The correct answer is B: 'To contract and cause goosebumps.' Arrector pili muscles are small muscles attached to hair follicles in the skin. When these muscles contract, they cause the hair to stand upright, resulting in the appearance of goosebumps. This physiological response is a remnant of our evolutionary past when our ancestors had more hair, and the raised hair helped to trap air for insulation or to make them look larger when threatened. Therefore, the function of arrector pili muscles is not to control sweat production (A), produce sebum (C), or sense touch (D), but rather to create the physical response of goosebumps.

3. A water fountain has a spherical base (diameter 50cm) and a cylindrical body (diameter 30cm, height 80cm) on top. What is the total surface area of the fountain (excluding the water surface)?

A. 3142 sq cm
B. 4712 sq cm
C. 5486 sq cm
D. 7957 sq cm

Correct answer: C

Rationale: Calculate the surface area of the sphere and the cylinder separately, then add them up.

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/sÂ²)

Correct answer: d

Rationale: Acceleration is measured in meters per second squared (m/sÂ²) in the SI unit system.

5. Which part of the brain controls balance and coordination?

A. Cerebellum
B. Hypothalamus
C. Occipital lobe
D. Corpus callosum

Correct answer: A

Rationale: Rationale: The cerebellum is the part of the brain responsible for coordinating voluntary movements, balance, and posture. It receives information from the sensory systems, the spinal cord, and other parts of the brain to regulate motor movements. The hypothalamus is involved in regulating various bodily functions such as temperature, hunger, and thirst. The occipital lobe is primarily responsible for processing visual information. The corpus callosum is a structure that connects the two hemispheres of the brain and facilitates communication between them.

6. What are the two main types of nuclear decay, and what differentiates them?

A. Fission and fusion, based on the size of the nucleus
B. Alpha and beta decay, based on the emitted particle.
C. Spontaneous and induced decay, based on the trigger.
D. Isotope decay and chain reactions, based on the stability of the nucleus.

Correct answer: B

Rationale: The two main types of nuclear decay are alpha and beta decay, based on the emitted particle. In alpha decay, an alpha particle (which consists of two protons and two neutrons) is emitted from the nucleus. In beta decay, a beta particle (either an electron or a positron) is emitted from the nucleus. These types of decay are differentiated by the particles they emit, rather than the size of the nucleus, trigger, or stability of the nucleus.