Question

Give a short note on the srtucture of bacteria and its various shapes.

Answer 1

Structure of a bacterial cell

• Bacterial cell has cell membrane, covered by strong rigid cell wall made up of peptidoglycan.
• In some bacteria, outside the cell wall there is an additional slimy protective layer called capsule made up of polysaccharides.
• The plasma membrane encloses the cytoplasm, incipient nucleus (nucleoid), ribosomes and DNA which serve as genetic material. Ribosomes are the site of protein synthesis.
• They lack membrane bound organelles.
• In addition to this, a small extra chromosomal circular DNA called plasmid is found in the cytoplasm.

Various shapes of Bacteria are
Shapes of bacteria Based on the shapes, bacteria are grouped as: 1. Spherical shaped bacteria called as cocci (or coccus for a single cell).
2. Rod shaped bacteria called as bacilli (or bacillus for a single cell).
3. Spiral shaped bacteria called as spirilla (or spirillum for single cell)