Mock p1 Flashcards
give 3 structural features found in all virus particles - and describe function of 1
-Protein capsid
-Genetic material
-Attachment proteins -function to bind to host cell receptors on the Th cells
explain why viruses are described as acellular and non-living
Viruses are not made from cells.
no cell membrane.
no metabolism.
Cannot respire
Why are antibiotics not effective against viruses
Do not have a cell wall.
Do not have any metabolic processes
What polysaccharide keeps the tracheal open in the tracheal system of an insect?
Chitin
Explain one important adaption of the gas exchange surface in tracheal system of an insect.
Tracheal wall thin / one cell thick, so rapid diffusion of gas into cells.
OR
Tracheal enter muscle fibres, so diff directly into cells.
Explain the importance of xylem being kept open as a continuous tube.
Allow unbroken water column.
Cohesion from H bonds between water molecules.
Evaporation/transpiration creates tension.
Describe two functions of the Golgi Apparatus in eukaryotic cells.
Modify/package/transport proteins.
Modify/package/transport lipids.
Forms/releases vesicles/lysosomes.
In Africa most population is resistant to malaria. Use your knowledge of natural selection to explain why this resistance is so common.
Mutation produces allel for resistance.
Those with allele more likely to survive and reproduce, so they pass on the allele for resistance.
Those without allele more likely to die and do not pass on allele. Over generations allele frequency increases.
Explain why damage to the cells lining the ileum reduces absorption and why this reduces absorption of water.
Reduces SA for absorption of the products of digestion.
This decreases the water potential in the ileum.
So water moves out of the cells by osmosis into the ileum.
Describe how an antibody would be digested if eaten.
Antibody is a protein.
Peptide bond hydrolysed.
Endopeptidases break internal peptide bonds.
Exopeptidases break terminal peptide bond.
Membrane bound dipeptidases break dipeptidases into amino acids.
What is the genome?
All the genes in an organism/ all the DNA in cell.
What is a proteome?
All the proteins an organism can code for.
Disadvantage of optical microscope?
Low resolution
How does a non competitive inhibitor cause enzyme to be inactive?
Inhibitor binds to enzyme on site that is NOT the active site.
This changes the shape of the AS.
So now the substrate is unable to bind to the AS as no longer complimentary.
Why do fused cells allow continuous production of MCaBs
Fused cells replicate rapidly and uncontrolled.
B cells produce MCaBs.
