Which objective lens requires oil to be applied?
Multiple choice.

Choice A rationale: Hypotonic is incorrect because hypotonic is a type of solution that has a higher concentration of water and lower concentration of solute than the cell placed in the solution. In a hypotonic solution, water moves into the cell and out of the solution by osmosis, causing the cell to swell.

Choice B rationale: Isotonic is correct because isotonic is a type of solution that has the same concentration of water and solute as the cell placed in the solution. In an isotonic solution, there is no net movement of water across the cell membrane.

Choice C rationale: Diffusive is incorrect because diffusive is an adjective that describes the movement of molecules from a region of high concentration to a region of low concentration, not a type of solution. Diffusion is the process by which molecules move across a membrane or a space due to their random motion.

Choice D rationale: Osmotic is incorrect because osmotic is an adjective that describes the movement of water across a semipermeable membrane, not a type of solution. Osmosis is the process by which water moves from a region of high water concentration to a region of low water concentration.

Choice E rationale: Hypertonic is incorrect because hypertonic is a type of solution that has a lower concentration of water and higher concentration of solute than the cell placed in the solution. In a hypertonic solution, water moves out of the cell and into the solution by osmosis, causing the cell to shrink.

Photosynthesis is the process by which plants, algae, and some bacteria use light energy to convert water and carbon dioxide into organic molecules, such as glucose, that can be used as food or building blocks for other molecules. Photosynthesis also releases oxygen as a by-product, which is essential for aerobic respiration in animals and other organisms.

Photosynthesis is the primary source of energy and organic matter for most living organisms on Earth, either directly or indirectly. Directly, photosynthesis provides food for the primary producers, such as plants and algae, that make their own food. Indirectly, photosynthesis provides food for the consumers, such as animals and fungi, that eat the primary producers or other consumers.

Photosynthesis also affects the global climate and the carbon cycle by removing carbon dioxide from the atmosphere and storing it in organic matter. Therefore, photosynthesis is the most important metabolic pathway of living organisms because its products have a significant impact on the biosphere.