If a protein is destined to be a part of the cell membrane or to leave a cell, describe how the protein is processed and transported to the cell membrane. Solution The cellmembrane is chemically made of phospholipoprotein that is combination of phospholipid and protein. Though protein is an integral part of plasma membrane, it allows certain protein to enter into the cell through p.m.. The protein is known as membrane transport protein..which is of two types that\'s carrier protein and channel protein. Carrier protein may be open or closed to both external environment or extracellular fluid and internal environment or intra cellular fluid but channel protein is always open to both the environment allowing entery of ions, molecules and solutes and solvent. Due to this reason p.m. is selectively permeable allowing some proteins in to the cell and restricting others. The carrier protein is either open or closed to both external environment and internal environment. Active transport is done by sodium potassium transport mechanism. ATP (adenosine tri phosphate) is needed for active transport. Active transport occurs against the concentration gradient. Lipid bilayer is generally not permeable. So active transport occurs with utilisation of ATP against concentration gradient. Another type of transportation is facilitated diffusion. It doesn\'t require any energy. Generally the polar bodies, the charged bodies and dissolve molecules pass through the membrane by this mechanism. The hydrophobic tail of lipid molecules opposes the movement of soluble molecules..

1. If a protein is destined to be a part of the cell membrane or to leave a cell, describe how the
protein is processed and transported to the cell membrane.
Solution
The cellmembrane is chemically made of phospholipoprotein that is combination of
phospholipid and protein. Though protein is an integral part of plasma membrane, it allows
certain protein to enter into the cell through p.m.. The protein is known as membrane transport
protein..which is of two types that's carrier protein and channel protein. Carrier protein may be
open or closed to both external environment or extracellular fluid and internal environment or
intra cellular fluid but channel protein is always open to both the environment allowing entery of
ions, molecules and solutes and solvent. Due to this reason p.m. is selectively permeable
allowing some proteins in to the cell and restricting others. The carrier protein is either open or
closed to both external environment and internal environment. Active transport is done by
sodium potassium transport mechanism. ATP (adenosine tri phosphate) is needed for active
transport. Active transport occurs against the concentration gradient. Lipid bilayer is generally
not permeable. So active transport occurs with utilisation of ATP against concentration gradient.
Another type of transportation is facilitated diffusion. It doesn't require any energy. Generally
the polar bodies, the charged bodies and dissolve molecules pass through the membrane by this
mechanism. The hydrophobic tail of lipid molecules opposes the movement of soluble
molecules.