The procedure to focus an image using a compound microscope involves

Correct Answer: B

Rationale: When using a compound microscope, it is essential to adjust the fine adjustment knob each time you switch to a new magnification level. The fine adjustment knob allows for precise focusing on the specimen at different magnifications, ensuring a clear and sharp image. The coarse adjustment knob is typically used only at the lower magnification settings to bring the image into view roughly. Adjusting the stage may be necessary based on the size and thickness of the specimen, but it does not need to be done every time a new magnification is selected. Therefore, option B is the correct choice as it focuses on the key aspect of precise focusing during magnification changes.

Correct Answer: D

Rationale: The correct answer is 'D: species.' In the biological hierarchical system of organization, a species is the least inclusive level. A species consists of organisms that share similar characteristics and can interbreed to produce fertile offspring. On the other hand, a phylum, order, and kingdom are more inclusive classifications that encompass multiple species. Phylum groups together related classes, order groups together related families, and kingdom groups together related phyla. Therefore, species is the least inclusive category within the biological hierarchical system.

Correct Answer: A

Rationale: Polarity is the most important characteristic of water because it results in hydrogen bonding, a high specific heat value, and its versatile solvent properties. These unique properties enable water to form hydrogen bonds with other substances, resist temperature changes, and dissolve a wide variety of solutes, making it essential for life processes. Choice B is incorrect because water exhibits hydrogen bonding, not covalent bonding. Choice C is incorrect as water does not form ionic bonds. Choice D is incorrect because water has a high, not low, specific heat value, which is vital for its role in temperature regulation.

Correct Answer: B

Rationale: The smooth endoplasmic reticulum (ER) is the organelle responsible for detoxifying multiple molecules in a cell. It contains enzymes that help break down toxins and drugs, making it an essential organelle for detoxification processes. The rough ER, lysosome, and Golgi apparatus do not play direct roles in detoxification. The rough ER is mainly involved in protein synthesis and transport. Lysosomes are responsible for digestion and recycling within the cell. The Golgi apparatus is involved in modifying, sorting, and packaging proteins for secretion or for use within the cell.

Correct Answer: C

Rationale: Metabolism is the sum of all chemical reactions that occur within an organism to maintain life. It involves all the processes that break down molecules to release energy (catabolism) and build new molecules to support growth and maintenance (anabolism). Respiration refers specifically to the process of generating energy from the breakdown of glucose molecules. Synthesis is the creation of complex molecules from simpler ones. Therefore, metabolism is the most comprehensive term that encompasses all these processes within an organism.