Cell Theory

Question 1

Archea properties

Answer 1

a prokaryote, ether linked lipids in cell membrane, no membrane bound organelles, circular chromosome extreme environment bacteria,

Question 2

Eubacter properties

Answer 2

Procaryote: lack a cell nucleus and other cell parts, and tend to be less complex,possess cell walls made of peptidoglycan, a chemical that gives their cell wall added strength, eg. Salmonella and ecoli

Question 3

Eukaryotes properties

Answer 3

Membrane bound organelles, have compartments, cytoskeleton

Question 4

Prokaryotes properties

Answer 4

sperical, rod, spiral, mycoplasma (smallest cells known), have a cell wall, DNA concentrated in one area, flagellum for propulsion, ribosomes in cytoplasm.

Question 5

Difference between Gram positive and negative

Answer 5

Positive: have a thick cell wall peptoglycan, so stain positively e.g.: Staphylococcus aureus: a bacterium known for MRSA, or methicillin-resistant Staphylococcus aureus.
Streptococcus pneumoniae: responsible for pneumonia.
Clostridium perfringens: which can cause a nasty case of diarrhea.

Gram-positive organisms have a thicker peptidoglycan cell wall compared with gram-negative bacteria. It is a 20-80nm thick polymer while the peptidoglycan layer of the gram-negative cell wall is 2 to 3nm thick and covered with an outer lipid bilayer membrane.

Negative: Bacteria with aa double membrane as do not take up dye: cytoplasmic membrane, a thin peptidoglycan layer, and an outer membrane containing lipopolysaccharide. periplasmic space

Eg. Escherichia coli, as well as many pathogenic bacteria, such as Pseudomonas aeruginosa, Neisseria gonorrhoeae, Chlamydia trachomatis, and Yersinia pestis.

Question 6

What is fluorescence microscopy

Answer 6

Excite molecules and emit at longer wavelength, GFP to visualise ongoing in cell (tag proteins)