WRONG ppqs Flashcards
vaccination vs immunisation
vaccination is injection of antigenic material
immmunisation is the porcess of developing immunity
lubdub caused by
LUB = av valves closing
DUB = semilunar valves closing
if the ion is necessary for the function what is it
PROSTHETIC GROUP
in what way does most water move across the root cortex
apoplast pathway
casparian strip contains …
(lignin)SUBERIN
how can facilitated diffusion NOT reqruie energy
- particles have their own kinetic energy
- move DOWN the concentration gradient
why cant glucose diffuse throguh membrane
- phospholipid bilayer acts as a barrier
- glucose molecules too large
- ALSO; glucose not soluble in phospholipid bilayer due to polar -OH groups
suggest how a water leaf is supported
- air spaces give buoyancy
- supoorted by surrounding water
sieve tube shape
hexagonal
purpose of disulfide bridge in antibodies
- hold hte ppcs (light chains and heavy chains) together
what is an autoimmunie disease (2)
- abnormal immune response
- agaisnt tissues normally in the body
how is water stil being lost even when stem is cut in potometer
evaporation
from leaf’s surface
sources of error in transporation experiment
- leaks in apparatus
- shoot not cut underwater
- error in reading position of meniscus
why is x described as ACTIVE immunity (3)
- lymphocytes activated
- antibodies produced
- memory cells remain
why is transpirartion inevtiable
- stomata open
- for gas exchange for photosynthesis
- photosynthesis necessary to make sugars for energy
- water potential gradient
- also some lost through waxy cuticle
advantage of stomata close during day for xerophytes
- transpiration occurs via stomata
- hotter during day, more evaporation. steeper wvp gradient
- shutting prevents loss
advantage of needles instead of leaves for xerophytes
- smaller SA
- less evaporation as fewer stomata
advtantage of hairs on epidermis
- hairs trap water vapour
- prevent wind from removing water vapour
- MORE HUMID AROUND LEAF SO
- reduce WVP gradient
for all xerophyte questions link to…
NEED TO CONSERVE WATER IN ENVIRONMENT
- and wvp gradient
transpiration defintion
- evaporation of water
- diffusion of water
- down a WP gradient via stomata
source and sink defintion
source: where assimilates are loaded into the phloem
sink: where assimilates are removed from phloem
explain how at different times the same plant root might be a source or a sink (2)
SOURCE: when root converts starch into sugars
SINK: when root stores starch
evidence of an active process (translocation)
ATP
many mitochondria in companion cells
against concentration gradient
6 marks for valid potometer set up
- cut healthy shoot underwater -> prevent air entering xylem
- cut shoot at a slant -> increase SA
- apparatus set up under water, full of water -> no air bubblles
- airtight/watertight joints
-dry leaves
3 MARKS - constant conditions
- time for shoot to acclimatise