1. A new invention claims to solve the energy crisis. What criteria should you use to evaluate this claim?

A. The inventor's qualifications and credentials.
B. The technology's cost-effectiveness and affordability.
C. Evidence of independent testing and scientific validation.
D. Testimonials from celebrities and public figures.

Correct answer: C

Rationale: When evaluating a claim about solving the energy crisis, it is crucial to look for evidence of independent testing and scientific validation. This ensures that the technology has been rigorously assessed and verified by experts in the field, providing credibility to the invention's effectiveness. Testimonials from celebrities and public figures (option D) may not provide reliable information about the technology's actual capabilities. The inventor's qualifications and credentials (option A) are important but do not guarantee the technology's success. Cost-effectiveness and affordability (option B) are significant factors but should be considered alongside scientific validation to assess the overall impact and feasibility of the invention.

2. Myelin sheath is a fatty substance that insulates and protects the long extensions of some nerve cells. It is produced by:

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

Correct answer: A

Rationale: The correct answer is A: Schwann cells. Schwann cells are a type of glial cell in the peripheral nervous system that produce the myelin sheath around axons. Myelin sheath is essential for the rapid conduction of nerve impulses and provides insulation and protection to nerve fibers. Astrocytes are glial cells that provide support and maintain homeostasis in the central nervous system, but they do not produce myelin. Neurons are the main functional units of the nervous system responsible for transmitting nerve impulses. Oligodendrocytes are another type of glial cell in the central nervous system that produce myelin sheath around axons in that region, not in the peripheral nervous system where Schwann cells are responsible for myelination.

3. The basic unit of communication in the nervous system is called a:

A. Neuron
B. Astrocyte
C. Neurotransmitter
D. Synapse

Correct answer: A

Rationale: The basic unit of communication in the nervous system is a neuron. Neurons are specialized cells that transmit information through electrical and chemical signals. They form complex networks to relay messages throughout the body. Astrocytes are support cells that help maintain the environment around neurons. Neurotransmitters are chemicals that transmit signals between neurons at synapses. A synapse is a junction between two neurons where communication occurs. However, the primary unit responsible for communication in the nervous system is the neuron, making it the correct answer.

4. The primary function of the placenta during pregnancy is to:

A. Produce insulin
B. Facilitate gas exchange between mother and fetus
C. Excrete waste products from the fetus
D. All of the above

Correct answer: D

Rationale: The correct answer is D, 'All of the above.' The placenta serves multiple crucial functions during pregnancy. It facilitates gas exchange between the mother and fetus, ensuring the transfer of oxygen and nutrients while removing carbon dioxide and waste products. Additionally, the placenta produces hormones like insulin that help regulate the mother's metabolism and support the development of the fetus. Therefore, the placenta plays a vital role in maintaining a healthy environment for the growing fetus by providing essential nutrients, removing waste, and regulating hormonal balance.

5. What is the function of the cell membrane?

A. To protect the cell and control what enters and exits
B. To store energy
C. To produce proteins
D. To synthesize lipids

Correct answer: A

Rationale: Rationale: The cell membrane, also known as the plasma membrane, serves as a protective barrier for the cell, separating the internal environment of the cell from the external environment. It is selectively permeable, meaning it controls the passage of substances in and out of the cell. This regulation of what enters and exits the cell is crucial for maintaining the cell's internal environment and ensuring proper functioning. Options B, C, and D are incorrect because storing energy, producing proteins, and synthesizing lipids are functions carried out by other cellular structures such as mitochondria, ribosomes, and endoplasmic reticulum, respectively, not the cell membrane.

6. How is power related to energy?

A. Power is the same as energy
B. Energy is the rate at which work is done
C. Power is the amount of stored energy
D. Energy is the rate at which power is transferred

Correct answer: b

Rationale: Energy is related to the amount of work done or the capacity to do work, while power measures the rate at which work is done or energy is transferred.