1. What is the difference between a ventral and dorsal root of a spinal nerve?

A. Ventral carries motor, dorsal carries sensory information.
B. Ventral carries sensory, dorsal carries motor information.
C. Ventral is larger, dorsal is smaller.
D. Ventral is located anteriorly, dorsal is posteriorly.

Correct answer: A

Rationale: The correct answer is A: 'Ventral carries motor, dorsal carries sensory information.' Ventral roots of spinal nerves contain motor fibers that carry signals from the central nervous system to muscles and glands, controlling movement and function. Dorsal roots, on the other hand, contain sensory fibers that transmit information such as touch, pain, and temperature from the peripheral nervous system to the central nervous system for processing. Understanding this distinction is crucial for comprehending how information is transmitted and processed in the nervous system.

2. Lysosomes are known as "suicide bags" of the cell. What enzymes do they contain?

A. Hydrolytic enzymes
B. Ligases (bonding enzymes)
C. Transferases (molecule transfer)
D. Oxidoreductases (redox reactions)

Correct answer: A

Rationale: Lysosomes are membrane-bound organelles containing hydrolytic enzymes responsible for breaking down various macromolecules, cellular waste, and foreign substances. These enzymes perform hydrolysis, a process where water molecules are used to break down larger molecules into smaller components. This function earned lysosomes the nickname 'suicide bags' as they can initiate cell death (apoptosis) by releasing their enzymes when needed. Ligases, transferases, and oxidoreductases are enzymes with different functions such as forming bonds, transferring molecules, and catalyzing redox reactions, respectively, which are not typically found in lysosomes. Therefore, the correct answer is A: 'Hydrolytic enzymes.'

3. A person is pushing a box across the floor. Which of the following forces is NOT doing work?

A. The person's pushing force
B. The normal force from the floor
C. The gravitational force on the box
D. The frictional force between the box and the floor

Correct answer: A

Rationale: Work is defined as the force applied in the direction of motion multiplied by the distance moved. Since the normal force acts perpendicular to the motion, it does not contribute to work.

4. The moon-shaped white structures at the base of fingernails are called:

A. Lunulae
B. Cuticle
C. Hyponychium
D. Matrix

Correct answer: A

Rationale: The correct answer is A, "Lunulae." The moon-shaped white structures at the base of fingernails are called lunulae. These are most visible on the thumb and are the visible part of the nail matrix. The lunulae appear white because the nail matrix underneath is not visible due to its thickness. Cuticle (B) refers to the thin layer of skin at the base of the nail, hyponychium (C) is the skin located under the free edge of the nail, and matrix (D) is the tissue at the base of the nail where growth occurs. Therefore, the correct term for the moon-shaped white structures is lunulae.

5. Which of the following is NOT a greenhouse gas?

A. Carbon dioxide
B. Water vapor
C. Nitrogen
D. Methane

Correct answer: C

Rationale: Rationale: A) Carbon dioxide: Carbon dioxide is a greenhouse gas that is naturally present in the Earth's atmosphere and is also released through human activities such as burning fossil fuels. B) Water vapor: Water vapor is a greenhouse gas that is naturally present in the atmosphere and plays a significant role in the Earth's climate system. C) Nitrogen: Nitrogen is not considered a greenhouse gas because it does not have the ability to absorb and emit infrared radiation in the same way that greenhouse gases like carbon dioxide and methane do. D) Methane: Methane is a potent greenhouse gas that is released through natural processes such as wetland decomposition and human activities such as livestock farming and fossil fuel extraction. Therefore, the correct answer is C) Nitrogen, as it is not a greenhouse gas.

6. Which of the following best describes a chemical change?

A. Melting ice to form water
B. Dissolving sugar in water
C. Burning wood to produce ash
D. Crushing a can to reduce its size

Correct answer: c

Rationale: Chemical changes involve the formation of new substances with different chemical properties. Burning wood involves a chemical reaction where wood undergoes combustion, breaking down its chemical structure to produce new substances like ash and gases.