Why is plasma membrane called selectively permeable?

Answer 1

Selective (or differential) permeability allows the cell to regulate its internal environment and maintain internal homeostasis. This is also the basis by which a neuron (nerve cell) can 'fire' and send a message along its axon - it selectively allows one electrolyte then a different electrolyte to flow across its cell membrane and change the electrochemical gradient.

Answer 2

Plasma membranes are described as being differentially permeable because they select what substances can pass through and what can not. Their behaviour is different for each substance. For example, the membranes will allow molecules such as water, carbon dioxide, oxygen and various small molecules to pass through. Larger molecules such as glucose and various ions are unable to permeate.

Answer 3

The plasma membrane is called selectively permeable because it allows certain substances to pass through while restricting the passage of others. This selectivity is due to the presence of proteins and lipid molecules that control the flow of substances into and out of the cell. This property helps the cell maintain internal balance and exchange essential molecules with its environment.

Answer 4

Because it can pass some liquids, minerals and water through it.

Answer 5

Differentially.

This means, in this context, that the cell membrane is semipermeable; letting some substances through and not letting some other substances through the membrane.