bacteria

Prokaryotic cellsBacteria

Choice CChoice E

https://www.youtube.com/watch?v=qOLbwJ9LGos

Part Structure Function

Cell wall 10-100nm thick. A multilayered structure made of peptidoglycan. May be gram negative or gram

positive

Protects the cell from bursting due to osmosis and maintains the shape of the

cell

Plasma membrane Phospholipids bilayer with proteins floating in membrane.

These can include enzymes for

respiration/photosynthesis

Controls to passage of substances in and out of the cell. Can be folded to give

extra surface area for respiration

Genetic material A loop of DNA Controls the cell`s activities

Plasmid A small circle of DNA. Contain genes which help the bacteria to survive in adverse

conditions. Can carry antibiotic resistance genes.

Capsule An outer protective layer Protects against chemicals and desiccation and protects the bacterium from attack by phagocytic cells, such as our

white blood cells. Helps bacteria to form colonies

Ribosome Small ribosomes The site of protein synthesis

Flagellum A rigid hollow cylinder of protein. When present they vary

in number between species

Used in the locomotion of motile bacteria

Microorganisms can cause disease by damaging the cells of the host and by producing toxins

Mycobacterium tuberculosis is a Gram-positive, rod-shaped bacterium and the cause of

tuberculosis in humans

Tuberculosis is primarily an airborne disease; it is spread from person to person

by droplet infection when an active TB sufferer coughs and sneezes

The most common salmonellosis is enterocolitis, caused principally by Salmonella enteriditis and

Salmonella typhimurium.

Food poisoning caused by S. enteriditis and S. typhimurium occurs when these bacteria are present in sufficient numbers in consumed food. A bacterial load of 100,000 per gram of food is

sufficiently high for many of the bacteria to survive the digestion process, and to continue multiplying within the gut.

Eukaryotic Cell

Has membrane bound organellesHas no membrane bound organelles

Cellulose based cell wall (where a cell wall is present)

Peptidoglycan based cell wall (where a cell wall is present)

DNA held on linear chromosomes DNA held on circular chromosomes

DNA located within the nucleus DNA contained within the cytoplasm

ATP production occurs in mitochondria

ATP production occurs in infolded regions of the cell surface membrane called mesosomes

Have a phospholipid bi-layer cell membrane

Has a nucleus Does not have a nucleus

Small RibosomesLarge (70S) Ribosomes

Ribosomes are the site of protein synthesis

May have undulipodia May have Flagella

Prokaryotic Cell