Notes:
1) Cell wall of bacteria is made up of peptidoglycan.
2) Cell wall of gram positive bacteria has thick peptidoglycan layer(90%) while cell wall of gram negative bacteria has few layers of peptidoglycan layer (10%).
3) Teichoic acid and lipoteichoic acid found on peptidoglycan layer and contribute to the acidicity of the gram positive cell wall.
4) The cell wall of gram negative bacteria consists of outer membrane.
5) Lipoprotein, lipopolysaccharide, phospholipid and porins are found on the outer membrane of gram negative bacteria.
6) The polysaccharide portion of LPS is O polysaccharide while the lipid portion is A lipid.
7) Atypical cell wall means no cell wall or little cell wall material.
8) Sterols are found on atypical cell wall which provide rigidity to the membrane.
9) Archaea cell wall has no peptidoglycan but contains pseudomureins.
10) Pseudomureins are linked by glycosidic bond beta(1,3) and consist of NAT.
11) Cell wall of Archaea is resistant to lysozymes and beta-lactam antibiotics but cell wall of bacteria is susceptible to lysozymes and beta-lactam antibiotics.
12) Plasma membrane acts as selectively permeable membrane. Hydrophilic ends are interact with water while hydrophobic ends are away from water.
13) Plasma membrane can synthesizes cell wall components, assists in DNA replication, carries on respiration and captures energy as ATP.
14) Plasmolysis: cells shrink ; Lysis: cells burst
15) Passive process not requires ATP and molecules are move along concentration.
16) Passive process includes simple diffusion, osmosis and facilitated diffusion.
17) In simple diffusion, substances move from high solute concentration to low solute concentration until equilibrium is reached.
18) In osmosis, water move from high concentration to low concentration.
19) In facilitated diffusion, substances moved by transporter proteins from high to low concentration.
20) Active process requires ATP and molecules are move against concentration.
21) In Group translocation, molecules are chemically modified during passage across cytoplasmic membrane.
22) The nucleoid are single long circular molecules of double-stranded DNA and not membrane-bounded and no histones surrounded.
23) Plasmid consists small circular, double stranded DNA but not essential DNA material. It have the resistant to certain antibiotics.
24) Ribosomes are used for protein synthesis and 70S ribosomes are made up of small subunits 30S and large subunits 50S.
25) Group translocation is exclusively for prokaryote.
Activities: Labelled the image of structure of prokaryote and stated the functions of each structure.
My own explorace:
1) Heating is one of the examples of mechanical breakage.
2) Gram negative bacteria are stronger compared to gram positive bacteria because outer membrane provides a barrier to certain antibiotic, detergent and heavy metals.
3) Degrading enzymes are those enzymes that can degrade macromolecules to monomers.
4) Porin consists enzymes that can degrade antibiotics. For example, bacteria synthesise beta-lactamase to develop resistance to beta-lactam antibiotic.
5) Exotoxin are stronger compared to endotoxin because endotoxin only released during lysis of the cell.
6) Mycoplasma pneumoniae is a human pathogen that causes the disease mycoplasma pneumonia and resistants to antibacterial agents.
7) Why does 70S ribosome written as 50S and 30S? S stands for svedberg unit. The svedberg is a measure of time. That's mean S is not the size or amount but is the rate of sedimention when those ribosomes are centrifuged.
Reflection on this topic:
What I can conclude from this topic is the cell wall of prokaryote is very important. Dr Wan kept mentioned the importance of cell wall because cell wall of bacteria can used to differentiate the pathogenicity of different bacteria. Before that I still wondered why 70S ribosome written as 50S and 30S....so now I finally got the answer after this lecture. Thanks Dr Wan..^^
No comments:
Post a Comment