1. The Merkel cells, located in the epidermis, are specialized for:

A. Melanin production
B. Temperature sensation
C. Touch perception
D. Immune defense

Correct answer: C

Rationale: The correct answer is C: 'Touch perception.' Merkel cells, also known as Merkel discs, are found in the skin's epidermal layer and are responsible for sensing touch. These cells are located near nerve endings and help detect light touch and pressure on the skin. They play a crucial role in the perception of tactile sensations and are not involved in melanin production, temperature sensation, or immune defense. Therefore, the specialized function of Merkel cells is primarily related to touch perception, making option C the correct choice.

2. The ball-and-socket joint, which allows for wide range of motion, is found in the connection between:

A. Upper arm and shoulder blade (scapula)
B. Collarbone (clavicle) and breastbone (sternum)
C. Two vertebrae in the spine
D. Ribs and sternum

Correct answer: A

Rationale: The correct answer is A: 'Upper arm and shoulder blade (scapula).' The ball-and-socket joint is found in the connection between the humerus (upper arm bone) and the scapula (shoulder blade). This joint allows for a wide range of motion, including flexion, extension, abduction, adduction, and rotation. The collarbone (clavicle) and breastbone (sternum) are connected by a cartilaginous joint, not a ball-and-socket joint. Two vertebrae in the spine are connected by facet joints, and the ribs and sternum are connected by cartilaginous joints and the costovertebral joints. Therefore, the ball-and-socket joint is uniquely found in the connection between the upper arm and the shoulder blade, allowing for the shoulder's impressive range of motion.

3. What is the formula for calculating density?

A. Density = Volume / Mass
B. Density = Mass Ã— Volume
C. Density = Mass / Volume
D. Density = Volume - Mass

Correct answer: c

Rationale: Density is defined as the mass of a substance divided by its volume. The formula for density is Density = Mass / Volume.

4. What is the measure of the total amount of space occupied by an object?

A. Mass
B. Density
C. Weight
D. Volume

Correct answer: d

Rationale: Volume is the measure of the total amount of space occupied by an object and is typically measured in cubic units such as cubic meters or liters.

5. Which type of glial cell provides structural support and insulation for neurons in the central nervous system?

A. Schwann cells
B. Astrocytes
C. Oligodendrocytes
D. Microglia

Correct answer: C

Rationale: The correct answer is C: Oligodendrocytes. Oligodendrocytes are a type of glial cell found in the central nervous system that provide structural support and insulation for neurons by forming myelin sheaths around axons. Schwann cells, on the other hand, are found in the peripheral nervous system. Astrocytes play a role in nutrient transfer and maintaining the blood-brain barrier. Microglia are responsible for immune defense and clearing debris in the CNS. Therefore, oligodendrocytes are specifically responsible for providing structural support and insulation for neurons in the central nervous system.