1. Which part of the neuron is responsible for transmitting signals away from the cell body and toward other neurons or muscles?

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

Correct answer: a

Rationale: The correct answer is 'A: Axon.' The axon is a long, slender projection of a neuron that carries nerve impulses away from the cell body towards other neurons or muscles. It acts as the primary transmission line of the nervous system, sending electrical signals known as action potentials. Dendrites, on the other hand, receive signals from other neurons and transmit them towards the cell body. The synapse is the junction between two neurons where communication occurs. The myelin sheath is a fatty substance that surrounds and insulates the axon, speeding up the transmission of nerve impulses. Therefore, the axon is specifically responsible for transmitting signals away from the cell body, making it the correct answer.

2. Frequent, painful urination is a common symptom of:

A. Diabetes
B. Urinary tract infection (UTI)
C. Kidney stones
D. All of the above

Correct answer: D

Rationale: The correct answer is D, 'All of the above.' Frequent, painful urination can be a symptom of various conditions affecting the urinary system. In diabetes, high blood sugar levels can lead to increased urine production. UTIs often cause painful urination due to the infection in the urinary tract. Kidney stones can also result in frequent and painful urination as they obstruct the flow of urine. Therefore, all three options can present with the common symptom of frequent, painful urination, making 'All of the above' the correct choice.

3. What is the correct way to write "25th anniversary" as a word?

A. Twenty-fiveth anniversary
B. Twenty Fiveth Anniversary
C. Twenty fifth anniversary
D. twenty-fifth anniversary

Correct answer: D

Rationale: Ordinals (numbers with "th", "st", "nd", etc.) are generally written as words when used before nouns. Option (d) is correct.

4. Decomposers in an ecosystem play a vital role by:

A. Photosynthesizing and producing organic matter
B. Breaking down dead organisms and returning nutrients to the environment
C. Preying on herbivores and controlling their populations
D. Fixing nitrogen from the atmosphere and making it available to plants

Correct answer: B

Rationale: Rationale: Decomposers are organisms that break down dead organic matter, such as dead plants and animals, into simpler substances. By doing so, they help to recycle nutrients back into the environment, making them available for other organisms to use. This process is essential for the functioning of ecosystems, as it ensures that nutrients are not lost but instead are continuously cycled through the ecosystem. Photosynthesis (option A) is the process by which plants and some other organisms convert light energy into chemical energy in the form of glucose, and it is not a role of decomposers. Preying on herbivores (option C) is a role typically carried out by predators, not decomposers. Fixing nitrogen from the atmosphere (option D) is a process carried out by nitrogen-fixing bacteria, not decomposers.

5. What is the name of the curved bone in the back that provides support and attachment for muscles?

A. Sternum
B. Scapula
C. Clavicle
D. Vertebral column

Correct answer: D

Rationale: The correct answer is D: Vertebral column. The vertebral column, also known as the spine or backbone, is a series of small bones called vertebrae that provide support and protection for the spinal cord. It also serves as an attachment point for various muscles in the back. The sternum, scapula, and clavicle are all bones in the upper body, but they do not specifically provide support and attachment for muscles in the back like the vertebral column does.

6. What is the difference between DNA and RNA?

A. Both are double-stranded.
B. DNA contains deoxyribose sugar, while RNA contains ribose sugar.
C. RNA contains the nitrogenous base uracil, while DNA contains thymine.
D. Both are identical molecules.

Correct answer: B

Rationale: Rationale: A) Incorrect. DNA is double-stranded, but RNA is typically single-stranded. B) Correct. DNA contains deoxyribose sugar, which lacks an oxygen atom on the 2' carbon of the sugar ring, while RNA contains ribose sugar, which has an additional hydroxyl group on the 2' carbon. C) Incorrect. RNA contains the nitrogenous base uracil, while DNA contains thymine. D) Incorrect. DNA and RNA have distinct structures and functions, so they are not identical molecules.