test corrections Flashcards
ventricular diastole events
pressure in ventricles decrease as it relaxes
semilunar valves shut
atria fills with blood
av valves open
blood enters ventricles
for valves to shut what do the tendons do
relax
smooth muscle function
allows contraction and dilation
changes diameter of human to control air flow
explain how an increase in co2 produces the Bohr effect and state the befit of this effect for the tissue
actively repairing tissue=more co2
increase in formation of carbonic acid and dissociation of carbonic acid and hydrogen ions is more hydrogen atoms bind to haemoglobin
more oxygen unloaded
affinity for oxygen decrease
more oxygen for respiration
adaptation of sieve tube element
no nucleus/phew organelles for maximum volume of space for assimilates
elongated cells to make sieve tubes
plasmodesmata unloading from companion cells
sieve plates to prevent bursting
sieve pores for flowing between sieve tube elements
adaptation of mesophyll cells
glucose lots of chloroplast to absorb sunlight
large vacuole to keep chloroplast at the periphery
thin cell wall for diffusion
isodiametric shape to prevent close packing
why is rate of transpiration greater during day than night
stomata is only open during the day to obtain co2 for photosynthesis which requires sun
most water is lost through stomata
how to mutations cause healthy cells to become tumour cells
mutton occurs for a gene controlling cell division eg proto-oncogene to oncogene
tumour suppressor gene turned off
disruption to cell cycle
uncontrolled division
to not respond to signals to stop dividing
role of mitosis in formation of blood cells
produce new blood cells
large numbers required to transport oxygen
produce genetically identical cells
replace dead cells
role of Golgi body in secretory cells
modifies and repackages proteins. folds polypeptidesthe protein that needs to be secreted attached to cis side and leaves trans side in a vesicle. travels in vesicle to cell membrane to be secreted
foramtion of lyossomomes
modification of lipids
