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3 years ago

What does it mean for a membrane to be selectively permeable?

Biology

2 answers:

Iteru [2.4K]3 years ago

4 0

The membrane is said to be semi permeable when <u>only certain molecules are allowed to pass through them</u>.

Further Explanation:

Semi-permeable membrane is the membrane which allows only a certain molecules to pass through them. This process is a type of diffusion generally does not require any external energy influence.

The diffusion takes place only of those molecules which are permeable through the membrane. This process is generally passive but can be sometimes active. One of the examples of biological semi permeable membrane is lipid bilayer which is the covering of several cells present in the body. It consists of hydrophobic head and hydrophilic tail which is embedded in the layer.

The bilayer is the mode of communication of the cell. External influence changes the structure of protein present in the layer and helps the cell to become selectively permeable. This is how the cell communicates with the surroundings.

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Answer Details:

Grade: High School

Subject: Biology

Chapter: Cells and osmosis

Keywords:

Membrane, semi permeable, diffusion, lipid bilayer, bilayer, communication of the cell, external energy, active transport, passive transport.

maw [93]3 years ago

3 0

Answer;

Semi-permeability means that only certain molecules are allowed to pass through.

Explanation;

-Semi-permeability is one of the features of a cell membrane, which means that the membrane allows selective movement of materials in and out of the cell; that is only certain molecules can enter or leave the cell.

-For example smaller molecules such water and ions such as potassium and sodium ions are able to leave and enter the cell, while other molecules that are large such as protein molecules can not enter or leave the cell.

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