Simple diffusion is the process by which a substance moves across a cell membrane from an area of high concentration to an area of low concentration. Substances that move by simple diffusion are able to diffuse directly across the phospholipid bilayer of the cell membrane. These substances are generally small and neutral, as large or charged particles cannot cross the phospholipid bilayer. Some examples of molecules that move by simple diffusion are carbon dioxide and oxygen.
Facilitated diffusion is the process by which a substance moves across a cell membrane from an area of high concentration to an area of low concentration with the aid of a membrane protein. Substances that move by facilitated diffusion are not able to diffuse directly across the phospholipid bilayer of the cell membrane. These substances are generally large and/or charged. They therefore travel through a protein channel in the cell membrane along their concentration gradient. Some examples of substances that can move by facilitated diffusion are glucose, sodium ions and chloride ions.
The similarities between facilitated diffusion and simple diffusion are:
They both involve the movement of a substance across a cell membrane along its concentration gradient (from an area of high concentration to an area of low concentration).
They are both examples of passive transport, as neither requires energy from the cell to move the substance across the membrane.
Answer:
Small intestine
Explanation:
It is in the small intestine where most food absorption occurs. Specifically, in the jejunum and the ileum. This is the site where nutrient absorption takes place too. Some water is also absorbed here, but the one mainly in charge of that is the large intestine.
Answer:
Could be multiple. C or A
Explanation:
Enzymes are required for respiration and respiration is exo thermic
<span>Letter A is the answer. Almost all plant cells have single large central vacuole. These large central vacuoles of the plant cells are filled with water and can take over 80% of its cell volume. This is surrounded by a single membrane called tonoplast. The role of the central vacuole is maintaining the plant cell's pressure.</span>
Answer:
It is called feedback regulation.
Explanation:
It is used when a product of the reaction is used for regulate the reaction. Therefore when there is enough product like ATP in this situtation, there is no need to run the reaction.
