BACTERIAL CELL STRUCTURE AND FUNCTIONS

Bacteria have functional structures that help it to live and survive in the environment that they live in.below are the structures and their specific functions; 

Flagellum- Flagella (singular: flagellum) are long, thin, whip-like appendages attached to a bacterial cell that allow for bacterial movement. it is attached to the cell by a structure called basal body that allows the flagellum to rotate as it causes motion. 

Pili - it is the first external structure of a bacterial cell (plural: pili). A pilus is a thin, rigid fiber made of protein that protrudes from the cell surface. The primary function of pili are to attach a bacterial cell to specific surfaces or to other cells

Capsule- It is a polysaccharide layer that lies outside the cell envelope, and is thus deemed part of the outer envelope of a bacterial cell. It is a well-organized layer, not easily washed off. : Capsules are anti-phagocytic. They limit the ability of phagocytes to engulf the bacteria. The smooth nature and negative charge of the capsule prevents the phagocyte from adhering to and engulfing the bacterial cell

Cell wall- it lies just under the capsule and its made up of peptidoglycan (also called murein), which is made from polysaccharide chains cross-linked by unusual peptides containing D-amino acids iving it a tough nature. it allows influx of some simple molecules. The primary function of the cell wall, however, is to maintain the cell shape and prevent bursting from osmotic pressure (called lysis).

Cell membrane- its made up of phospholipid bi-layer and its main function is to provide site for passage of molecules in and out of the cell. 

Ribosome- its a protein molecule with RNA material and forms the site for the manufacture of cell proteins. 

Cytoplasm- The cytoplasm, or protoplasm, of bacterial cells is where the functions for cell growth, metabolism, and replication are carried out. It is a gel-like matrix composed of water, enzymes, nutrients, wastes, and gases and contains cell structures such as ribosomes, a chromosome, and plasmids.

Chromatin - its genetic material that contains chromosomes that make up bacterial DNA. chromatin's function is to safely keep the chromosomes and to aid in mitosis and meiosis  during cell division.

Bacterial diet 

Bacteria have a wide range of diets. Some are heterotrophs (they eat other organisms) and others are autotrophs (they make their own food).

Most heterotrophic bacteria are saprobes (they absorb dead organic material like rotting flesh). Some of these parasitic bacteria kill their host while others help their host.

Autotrophic bacteria make their own food, either by photosynthesis (which uses sunlight, carbon dioxide and water to make food) or by chemosynthesis (which uses carbon dioxide, water and chemicals like ammonia to make food - these bacteria are called nitrogen fixers and include the bacteria found living in legume roots and in ocean vents

Bacterial survival

The bacteria are unicellular microorganisms that are independent of humans or other organisms. However, humans need them for survival. Bacteria in the gut help to breakdown food, and one species that lives symbiotically in the large intestine manufactures’ vitamin K, an essential blood clotting factor. However, when overactive, bacteria cause diseases like dental carries, peptic ulcers, and respiratory infections. Bacteria live in harsh environments and they in turn have developed some basic mechanisms to enable them survive;

i)   Cell wall- its structurally hard and gives the bacteria its shape. Also helps it to avoid increasing past its original size when in an hypotonic environment.

ii)  Cell capsule- protects it from chemical damage by acids and bases and from phagocytosis by other organisms.

The ribosomes (like 16s, 30s, 50s and 70s) are essential n the survival of the bacteria since they manufacture the proteins that form part of the cell wall and capsule. This results in inhibited reproduction, returded growth and later death of the bacteria.

Bacteria also produce enzymes (e.g bacterial kinases and collagenases) that help it to digest materials in its environment to allow it to move and spread to other regions,

CLASSIFICATION OF ANTIBIOTICS

leukemia, para-cervical block, complete blood count