Question

Select the correct option: Cell recognition and adhesion are facilitated by components of the plasma membrane. These components are generally.
(a)protein molecules alone
(b)lipids alone
(c)both lipids and proteins
(d)glycolipids and glycoproteins.

Answer 1

Hint: Proteins have very specific shapes which make them ideal as receptor molecules for chemical signaling between cells. In the fluid mosaic organization’ the carbohydrates are entirely outside the lipid bilayer.

Complete answer:
Branching side-chain glycolipids and glycoproteins on the outer surface of cell membranes are involved in cell-cell recognition. In the fluid mosaic organization, carbohydrates are entirely outside the lipid bilayer. They bind with lipids or proteins, forming glycolipids and glycoproteins. Also, they are thought to undergo cross-linking between themselves to form a network. This helps the membrane components to anchor to each other to restrict their lateral movements. These molecules coordinate the molecular interactions on the cell surface for cell recognition, adhesion, and communication, and play a significant role in the normal existence and functioning of the cell.

Additional Information: -Glycolipids and Glycoproteins form hydrogen bonds with the water molecules surrounding the cell. Thus they help to stabilize the structure of the plasma membrane.
-Glycoproteins are involved in the immune system. They allow white blood cells to move around the body, to initiate immune responses, and identify other cells. They are also involved in creating mucus, which protects various organs in our body.
-Glycoproteins play an important role in keeping our bodies healthy and functional!
So, the correct answer is' Glycolipids and glycoproteins'.

Note: -Plasma membrane is primarily concerned with the regulation of entry and exit of ions and molecules into and out of the cell. This in turn depends upon its permeability properties.
-Plasma membrane is a porous, elastic, and selectively permeable living membrane, with lipoprotein composition, semi-fluid consistency, and laminar or micellar organization.
-According to the fluid mosaic concept of Singer and Nicholson, phospholipid molecules have continuous arrangements. They are arranged side by side and back to back in two parallel rows, forming a continuous lipid bilayer.