11 Flashcards
(31 cards)
agglutination
specific antibodies bind to antigens on pathogens and clump them together
opsonisation
▪︎marking pathogens
▪︎ so phagocytes recognise and destroy the pathogen more efficiently
antigenic variability
》gene mutation in the antigen
》that may lead to change in tertiary structure of antigen complementary to specific B cells
》so no longer complementary
herd immunity
if 85% individuals vaccinated then there’s little chance of disease spreading
so even non-vaccinated individuals will be protected
give a mutagenic agent
virus and bacteria
types of mutations
chromosomal
inverse
duplication
translocation
what’s chromosome non-dijunction
when pair of chromosomes fail to separae during metaphase 1
or
sister chromatids fail to separate in metaphase 2
cause of dawn syndrome
mitotic index=
number of cells in mitosis/total number of visible cells
how’s metabolic rate measured?
oxygen consumption
CO2 production
haemoglobin definition
protein with a quarternary structure
made up of 4 polypeptide chains
(2 alpha and 2 beta)
each Hb can combine with 4 oxygens
when less oxygen available then 3 2 or 1 may be taken up
percentage saturation of Hb with oxygen =
cardiac output=
(units= dm3 min-1)
stroke volume x heart rate
cardiac output= vol of blood expelled out of left ventricle per min
stroke volume= vol of bloof expelled from left ventricle in one cardiac cycle
heart rate= number of cardiac cycles per minute
atherosclerosis
process of narrowing or blocking arteries/arterioles
usually after damaged caused to artery wall for some reason
(eg. high BP)
risk factor in coronary heart disease
▪︎age
▪︎gender
▪︎genetic factors
▪︎smoking
▪︎stress
▪︎high lipid/cholesterol diet
what’s negative pressure?
water under tension
(the more nagative pressure, the more tension)
when to use median and when to use mean?
if wide range of values and outliers then use median
how to calculate area of leaf
draw around leaf on a graph paper
count number of squares
epidermis
outside membrane
endodermis
inner membrane
why is leafy shoot cut diagonally underwater
prevents damage to xylem
ensure continuous column of water
why is water prevented from getting on leaves
Aby water on the leaf could prevent loss of water vapour
through the stomata
why made sure that there’s no air bubbles
prevent air entering xylem
ensures continuous column of water
why joints sealed with waterproof jelly?
prevent water loss from potometer
prevent air from entering
why student soaked root tips in HCl
-hydrolise cellulose cell wall
-allows stain to diffuse into cells
-to stop mitosis
