paper 1 as 2020 Flashcards
(18 cards)
describe the biochemical test for non reducing sugar
-heat with acid (HCL) and neutralise
-heat with benedicts reagent in water bath for 5mins 80+
- turns red
phospholipid head
hydrophillic - passes through
phospholipid tail
hydrophobic - bilayer
what property of water prevents temperature increase in cells
-HIGH specific heat capacity
-buffers changes in temperature
describe how a phagocyte destroys a pathogen present in the blood
- engulfs it by endocytosis
- forming vesicle and fuses with lysosome
-enzymes digest hydrolyses it
what is the role of disulfide bridges forming quaternary structure of antibody
joins two polypeptides
organelles that help in the production of proteins
rer - produces protein
dna - code for protein
mitchondria - produces atp for protein synthesis
golgi apparatus - packages and transports
vesicles - transport
suggest why organelle x isnt visible
- nucleus i another part of the cell
-stain isnt on the nucleus
one advantage of tem instead of sem
-can view internal structures
-higher resolution
describe and explain the mechanism that causes lungs to fill with air
- diaphragm contracts and external intercostal muscles contract
- thoracic cavity increases, pressure in lungs decreases
3.air moves down pressure gradient
suggets why a stain was used on dna to stain tissue and not iodine that stains starch
-nucleus contains DNA
- animal tissue doesn’t contain starch
describe how mrna is produced from an exposed template strand of DNA
- free RNA nucleotides form complementary base pairs
-phosphodiester bonds form
-by action of RNA polymerase
define the term exon
base sequence that codes for a polypeptide
binary fission
replication of circular DNA
replication of plasmids
cytoplasm divides to form daughter cells
