bacteria
TRANSCRIPT
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