Answer the following

Explain the structure of a typical bacillus?

Bacteria are the smallest microorganisms present everywhere on the Earth and thus considered as cosmopolitan. They have a unique structure because of which they can resist high temperature and high pH.

● CAPSULE: This is the thick protective covering present on certain bacteria. The capsule is made up of polysaccharides. It protects the bacteria from drying out.

● CELL WALL: Cell wall of typical bacteria is made up of peptidoglycan, a protein- sugar complex. It gives the bacteria the perfect shape and provides support and rigidity. It contains pili and flagella which help in movement and anchorage.

● CELL MEMBRANE: It is the universal membrane present in all the cells. It is selectively permeable in nature. It controls the movement of substances in and out of the cell.

● CYTOPLASM: It is the main place where all the important functions of bacteria take place. It is a gel like matrix composed of water, enzymes and nutrients. It also contains cell structures like ribosomes, chromosomes and plasmids.

● FLAGELLA: They are the hair like structures which help in locomotion. Bacteria can be of many types depending upon the number of flagella and the type of flagella present.

● PILI: They are the hair like projections present on the surface of bacteria. They are usually many in number and are small as compared to flagella. They usually help in attachment. Specialized pili like sex pili are used for conjugation.

● NUCLEOID: This is the region where the chromosomal DNA is located. Bacteria do not have a membrane bound nucleus but simply an area where DNA strands are present. Most of the bacteria have a single, circular chromosomal DNA.

● RIBOSOMES: They are also known as the ‘protein factories’ of the cell. In bacteria, the ribosomes are of 70s type. They translate the genetic code from molecular language to amino acids.