NEET BIOLOGY

Detailed explanation-1: -Two types of surface appendage can be recognized on certain bacterial species: the flagella, which are organs of locomotion, and pili (Latin hairs), which are also known as fimbriae (Latin fringes). Flagella occur on both Gram-positive and Gram-negative bacteria, and their presence can be useful in identification.

Detailed explanation-2: -Also, flagella are seen in gram negative and gram positive bacteria and originate from the cell wall, pili are seen in gram negative bacteria and originate from the cytoplasmic membrane.

Detailed explanation-3: -Many Gram-positive and Gram-negative bacterial species and also Archaea as well as some eukaryotic cells have a flagellum (’whip’ in Latin). Flagellum is primarily a motility organelle that enables movement and chemotaxis.

Detailed explanation-4: -Pili can be found evenly around the surface of the cell, or localized to one or both of the poles. They are typical of Gram-negative bacteria, but can be found in Gram-positive bacteria and archaea as well.

Detailed explanation-5: -Prokaryotes often have appendages (protrusions) on their surface. Flagella and some pili are used for locomotion, fimbriae help the cell stick to a surface, and sex pili are used for DNA exchange. Most prokaryotic cells have a single circular chromosome.