Question

Is a protein pump active or passive?

Answer 1

Transport mechanism:

The movement of molecules across the membrane takes place through different mechanisms. Type of transport depends upon energy requirement-

1. Passive transport
2. Active transport

Passive transport:

It is the diffusion of molecules across the membrane without the expenditure of energy and is a spontaneous process. The diffusion takes place along the concentration gradient that is from higher concentration to lower concentration. It involves two mechanisms-

1. Simple diffusion
2. Facilitated diffusion

Simple diffusion:

1. In this process movement of molecules occurs along the concentration gradient until it becomes equal throughout the body/space.
2. This process requires no energy requirement for the movement of molecules.
3. Some examples can be the diffusion of gas in a room.

Facilitated diffusion:

1. This process involves a membrane transport channel that helps the movement of molecules.
2. Channels are glycoproteins that allow the movement of molecules across the membrane and are molecule specific.
3. Some examples are GLUT 4 which is involved in diabetes. It is a glucose transporter and allows glucose to be absorbed by the blood.

Active transport:

1. This process involves the movement of molecules against a concentration gradient that is from lower concentration to higher concentration.
2. It requires a source of energy in the form of ATP.
3. This mechanism will always require career assistance in which protein moves the molecule against the concentration gradient also called protein pumps.
4. One of the noticeable examples is the sodium-potassium pump in which ions are moved inside and outside the cells.