CONTENT
◉Eukaryote. Answer: Contain a nucleus and membrane bound
organelles.
◉Flagella. Answer: Used for locomotion or taxis in response to
photo or chemical stimuli. The distribution can be mono-, lopho- or
amphitrichous in nature. Spirochetes have periplasmic versions,
which are coiled around the length of the bacterium.
◉Pili. Answer: External bacterial structure used in conjugation
which is the exchange of DNA.
◉Fimbriae. Answer: An external bacterial structure used for
attachment. They provide adhesion, but not locomotion, and allow
bacteria to stick to each other and surfaces. They may be responsible
for the formation of biofilms and pathogenicity in bacteria.
◉S layer. Answer: Single layer of protein used for protection and/or
attachment.
, ◉Capsule. Answer: Compact covering that helps cells hide from the
immune system.
◉Slime layer. Answer: Loose covering which helps in the formation
of biofilms.
◉Cell envelope. Answer: All bacteria have this structure that
surrounds the cell and offers protection against the outside world.
The structure is composed of the cell wall and the cell membrane.
◉Cell Wall. Answer: A semi-rigid structure surrounding the cell that
provides structure and cellular shape.
◉Cell membrane. Answer: This structure is composed of a lipid
bilayer embedded with proteins. Selective permeability allows water
and small uncharged molecules to diffuse freely. Special carrier
mechanisms exist for the passage of most molecules, energy
reactions, nutrient processing, and discharge of wastes.
◉Gram-positive bacteria. Answer: The bacteria have a thick
peptidoglycan layer, an inner cell membrane, and special lipids,
teichoic acid, and lipoteichoic acid, in their cell walls. These cells
appear purple after the Gram staining procedure.