Question

name____ class__ date____
facilitated diffusion

1. what happens during the process of facilitated diffusion?
2. what is the role of protein channels in the cell membrane?
3. is the following sentence true or false? facilitated diffusion does not require the cell to use energy.

active transport

1. the energy - requiring process that moves material across a cell membrane against a concentration difference is called
2. is the following sentence true or false? active transport always requires transport proteins during the process.
3. complete the table about types of active transport.

types of active transport

type	description

|endocytosis|
|phagocytosis|
|exocytosis|

1. during endocytosis, what happens to the pocket in the cell membrane when it breaks loose from the membrane?

Explanation:

1. In facilitated diffusion, molecules move across the cell membrane from high - to low - concentration with the help of transport proteins (channel or carrier proteins).
2. Protein channels in the cell membrane provide a pathway for specific molecules (such as ions or small polar molecules) to cross the non - polar lipid bilayer of the membrane.
3. True. Facilitated diffusion is a passive transport process and does not require the cell to expend energy (ATP).
4. The energy - requiring process that moves material across a cell membrane against a concentration difference is called active transport.
5. True. Active transport always requires transport proteins to move substances against their concentration gradient.

25.

• Endocytosis: The cell membrane forms a pocket around the substance to be taken in, which then pinches off to form a vesicle inside the cell.
• Phagocytosis: A type of endocytosis where large particles (such as bacteria or dead cells) are engulfed by the cell. The cell membrane extends around the particle and encloses it in a vesicle.
• Exocytosis: A process where vesicles inside the cell fuse with the cell membrane and release their contents outside the cell.

1. During endocytosis, when the pocket in the cell membrane breaks loose from the membrane, it forms a vesicle inside the cell that can then be transported to other parts of the cell or fused with other organelles.

Answer:

1. Molecules move across the cell membrane from high - to low - concentration with the help of transport proteins.
2. Provide a pathway for specific molecules to cross the cell membrane.
3. True
4. Active transport
5. True
6. Endocytosis: Cell membrane forms a pocket and pinches off to create a vesicle. Phagocytosis: Engulfs large particles by extending the cell membrane. Exocytosis: Vesicles fuse with the cell membrane to release contents outside.
7. It forms a vesicle inside the cell.