1. Which part of the neuron receives incoming signals from other neurons and conducts them toward the cell body?

A. Axon
B. Dendrite
C. Synapse
D. Myelin sheath

Correct answer: b

Rationale: The correct answer is B: Dendrite. Dendrites are the part of the neuron that receive incoming signals from other neurons and conduct them toward the cell body. They play a crucial role in communication between neurons by receiving neurotransmitters released from neighboring neurons. Axons transmit signals away from the cell body, synapses are the junctions where neurons communicate with each other, and myelin sheath is a fatty insulation that surrounds and protects axons. Therefore, in this scenario, dendrites are specifically responsible for receiving and conducting incoming signals towards the cell body.

2. The main function of the nephrons is to:

A. Store urine
B. Filter blood and remove waste products
C. Produce hormones
D. Control blood pressure

Correct answer: B

Rationale: The correct answer is B: 'Filter blood and remove waste products.' Nephrons are the functional units of the kidneys responsible for filtering blood to remove waste products, excess ions, and water, while reabsorbing essential substances like glucose and amino acids. This process forms urine, which is stored in the bladder before being excreted. Options A, C, and D are incorrect because nephrons do not store urine, produce hormones, or directly control blood pressure; although the kidneys do play a role in long-term blood pressure regulation through mechanisms like the renin-angiotensin-aldosterone system.

3. Nervous tissue is responsible for

A. Movement
B. Protection
C. Communication and coordination
D. Nutrient transport

Correct answer: C

Rationale: Nervous tissue is responsible for communication and coordination within the body. This tissue includes neurons and supporting cells, which work together to transmit electrical signals and information throughout the body. Movement is primarily controlled by the muscular system, protection is the role of the immune system and skin, while nutrient transport is primarily handled by the circulatory system. Therefore, the correct answer is C: 'Communication and coordination.'

4. Which of the following is an example of an unsaturated fatty acid?

A. Stearic acid
B. Palmitic acid
C. Oleic acid
D. Butyric acid

Correct answer: C

Rationale: Oleic acid is an unsaturated fatty acid, containing at least one double bond in its hydrocarbon chain. The other choices are saturated fatty acids.

5. The process by which two or more species reciprocally influence each other's evolution through selection pressures exerted on one another is called:

A. Convergent evolution
B. Divergent evolution
C. Coevolution
D. Coevolution

Correct answer: C

Rationale: Rationale: A) Convergent evolution refers to the process by which unrelated species evolve similar traits due to similar environmental pressures. This does not involve reciprocal influence between species. B) Divergent evolution refers to the process by which two or more related species become more dissimilar over time due to different selection pressures. This also does not involve reciprocal influence between species. C) Coevolution is the process by which two or more species reciprocally influence each other's evolution through selection pressures exerted on one another. This can lead to a close ecological relationship between the species, such as in predator-prey interactions or mutualistic relationships. D) This option is a duplicate of option C.

6. What is the name of the bone marrow cavity in the long bones where red blood cells are produced?

A. Periosteum
B. Diaphysis
C. Medullary cavity
D. Epiphysis

Correct answer: B

Rationale: The correct answer is B: Diaphysis. The diaphysis is the shaft of a long bone where the medullary cavity is located. The medullary cavity is the central cavity of the diaphysis where red bone marrow is found and is responsible for producing red blood cells, white blood cells, and platelets. The periosteum is a dense membrane covering the outer surface of bones, not where red blood cells are produced. The epiphysis refers to the ends of long bones, while the medullary cavity is found in the diaphysis. Therefore, the correct choice is the diaphysis where the medullary cavity is located for red blood cell production.