EVERYDAY SCIENCE

Detailed explanation-1: -The bacteria cell envelope is a complex multilayered structure that serves to protect these organisms from their unpredictable and often hostile environment. The cell envelopes of most bacteria fall into one of two major groups.

Detailed explanation-2: -The outer layer of the bacterial cell is called cell wall, which is composed of a polymer matrix named peptidoglycan. Depending on the structure and the thickness of the cell wall, bacterial cell is classified into two groups: Gram positive and Gram negative bacteria.

Detailed explanation-3: -Cell Wall Peptidoglycans: Both Gram-positive and Gram-negative bacteria possess cell wall peptidoglycans, which confer the characteristic cell shape and provide the cell with mechanical protection.

Detailed explanation-4: -Capsule or slime layer is used to describe glycocalyx which is a thin, high molecular weight secretory substance present in many bacteria external to cell wall (Fig. 7.6). It is composed of polysaccharide, polypeptide, or both.

Detailed explanation-5: -One key bacterial adaptation is the capsule, an outer layer of polysaccharides that covers the cells of many different bacterial species. Capsules act as a sort of magic cloak, protecting bacteria from toxic compounds and desiccation and allowing them to adhere to surfaces and to escape the immune system of the host.