Question

Endocytosis is a way substances can ____________ a cell. During endocytosis, an intracellular ____________ forms to take in substances. Endocytosis occurs in several different ways. Phagocytosis occurs when substances to be transported into the cell are ____________ . Digestion occurs when the resulting vacuole fuses with a ____________ . Pinocytosis occurs when a ____________ , such as a polypeptide, is transported into the cell through a vesicle. Receptor-mediated endocytosis is a form of pinocytosis where molecules first bind to ____________ receptor proteins, which migrate to or are already in a coated pit. Exocytosis is a way substances can ____________ a cell. During exocytosis, a vesicle fuses with the plasma membrane as ____________ occurs. The ____________ often produces the vesicles that carry these cell products to the membrane.

Answer 1

Answer:

There is a large number of questions, and needed answers in this one, so, here are the answers and a short explanation:

1. Endocytosis is a way substances can enter a cell. That is the very definition of it. Endocytosis is the way that certain substances enter the cell. There are three types: receptor-mediated endocytosis, phagocytosis and pinocytosis.

2. During endocytosis, an intracellular: vacuole, forms to take in substances. Vacuoles are small vesicles that form when the plasma membrane surrounds a substance that will enter the cell.

3. Phagocystosis occurs when substances to be transported into the cell are cellular debris, or cells themselves, like is the case of invading microorganisms, and which will be destroyed by the cell, instead of taken in by the cell.

4. Digestion occurs when the resulting vacuole fuses with a: lysosome. Lysosomes are the ones responsible for appropriately handling the substance inside vacuoles, through digestion.

5. Pinocytosis occurs when a macromolecule, such as a lipid, has to enter the cell to be digested and used by the cell.

6. Receptor-mediated endocytosis is a form of pinocytosis where molecules first bind to plasma membrane transport receptor proteins, or carriers... These proteins on the membrane are responsible for protein-mediated transport of macromolecules who cannot simply cross the membrane.

7. Exocytosis is a way substances can be secreted out of a cell. It is the opposite of endocytosis.

8. During exocytosis, a vesicle fuses with the plasma membrane as release of the substance in the vesicle, occurs. During this time, the vesicle, which is a pouch-like formation much like the plasma membrane, fuses with the actual membrane and releases its contents to the extracellular space.

9. The Golgi apparatus often produces the vesicles that carry these cell products to the membrane. Usually these are protein-like substances, like enzymes. It is the Golgi who produces these vesicles and in the process produces proteins that will help to renovate the plasma membrane of the cell.