What does the term motile mean?

Choice A rationale: Microwaves are a type of electromagnetic radiation with low energy and long wavelengths. They are not absorbed by plants for photosynthesis, but rather pass through them or are reflected by them¹.

Choice B rationale: Infrared is a type of electromagnetic radiation with low energy and long wavelengths. It is not absorbed by plants for photosynthesis, but rather heats up the plant tissues or is reflected by them².

Choice C rationale: Gamma rays are a type of electromagnetic radiation with high energy and short wavelengths. They are not absorbed by plants for photosynthesis, but rather damage the plant cells or are blocked by the atmosphere³.

Choice D rationale: Ultraviolet is a type of electromagnetic radiation with high energy and short wavelengths. It is not absorbed by plants for photosynthesis, but rather harms the plant pigments or is filtered by the ozone layer⁴.

Choice E rationale: Visible light is a type of electromagnetic radiation with moderate energy and wavelengths. It is the only form of electromagnetic radiation that is absorbed by plants for photosynthesis, specifically by the pigments such as chlorophyll and carotenoids in the photosystems⁵. Visible light consists of a spectrum of colors, ranging from violet to red, and plants use different colors for different aspects of photosynthesis⁶.

Red blood cells are animal cells that lack a cell wall, a rigid structure that surrounds the cell membrane of plant cells, such as Elodea cells. A cell wall provides support and protection for the cell, and prevents excessive water uptake or loss. Red blood cells, on the other hand, rely on the osmotic balance of their environment to maintain their shape and function. If red blood cells are placed in a hypotonic solution, where the water concentration is higher outside than inside the cell, they will swell and burst due to osmosis. This is called hemolysis. If red blood cells are placed in a hypertonic solution, where the water concentration is lower outside than inside the cell, they will shrink and lose their ability to carry oxygen. This is called crenation.

Elodea cells, however, can withstand hypotonic or hypertonic solutions without bursting or shrinking, because their cell wall prevents the water from entering or leaving the cell beyond a certain point. Therefore, a major difference between red blood cells and Elodea cells is that Elodea cells have a cell wall, which protects them from bursting.