NEET BIOLOGY

Detailed explanation-1: -Bacteria are classified into five groups according to their basic shapes: spherical (cocci), rod (bacilli), spiral (spirilla), comma (vibrios) or corkscrew (spirochaetes). They can exist as single cells, in pairs, chains or clusters.

Detailed explanation-2: -The three basic shapes of bacteria are bacillus (rod-shaped), coccus (spherical-shaped), and spirillum (spiral-shaped).

Detailed explanation-3: -Bacteria are prokaryotes, lacking well-defined nuclei and membrane-bound organelles, and with chromosomes composed of a single closed DNA circle. They come in many shapes and sizes, from minute spheres, cylinders and spiral threads, to flagellated rods, and filamentous chains.

Detailed explanation-4: -Bacteria are microscopic single-celled organisms. The bacteria are usually of four types: Cocci (spherical bacteria), Bacilli (rod-shaped bacteria), Spirilla (spiral or twisted bacteria), Vibrio(comma-shaped).

Detailed explanation-5: -Bacterial names are based on the binomial system: the first name is the genus, the second name is the species. When written, the genus name is capitalized and the species name is not. Both genus and species names are italicized (e.g., Escherichia coli). A genus is a group of related species.