Topic 3B- More Exchange and Transport Symptoms Flashcards
what vessel carries blood away from the heart
arteries
do arteries have thick walls
yes
what type of blood do arteries carry
oxygenated
what is the only artery that carries deoxygenated blood
pulmonary artery
what do arteries divide up into
arterioles
what do the muscles in arterioles do
control direction where blood is demanded
what is the widening of the lumen
vasodilation
what is the lumen getting smaller
vasoconstriction
where do veins carry blood to
back to the heart
do veins have a small lumen
no, it’s wider than arteries
what has more elastic tissue for stretch and recoil to maintain pressure
arteries
do veins have valves, if so why
yes, to prevent backflow when going against gravity to the heart
what type of blood do veins carry
deoxygenated
do veins have muscle surrounding them, if so why
yes, this is to aid the low pressure blood back to the heart against gravity
what do arterioles branch into
capillaries
what is the smallest blood vessel
capillaries
why are capillary’s good for exchanging substances between cells and capillaries
they are 1 cell thick
what are capillary beds
network of capillaries in tissue
why is there a large number of capillaries
increase surface area for exchange
example of capillaries lining cells
surrounding the alveoli for gaseous exchange
where does photosynthesis happen
chloroplasts
what does the phloem transport
solutes- minerals and inorganic ions
why does the phloem transport solutes and what is the process called
for metabolic process and translocation
why do cells require glucose
for respiration
do all cells need the same amount of glucose
no the amount depends on their function and whats its then used for
what are the 3 main components of a phloem structure
sieve tube elements, end plates and companion cells
what are sites of production within a plant called
sources
where from the pants sources are the substances taken
sinks
how are sugars in a plant produced
photosynthesis
what does the mass flow theory rely on for movement
pressure gradients
(at source) phloem loading
in the mass transport theory, when the source pruduces sugar, what does this do to the concerntration
increases it
(at source) phloem loading
in the mass transport theory, how does the sugar move from the leaf cell to the companion cell
facilitated diffusion
(at source) phloem loading
in the mass transport theory, what does the cell actively transport into the sieve tube elements from companion cells
hydrogen ions
(at source) phloem loading
in the mass transport theory, how does the sugar get into the S.T.E from companion cells
co-transport with H+ ions
(at source) phloem loading
in the mass transport theory, what happens to the water potential in the phloem once the sugar has been pumped into the phloem
decreases
(at source) phloem loading
in the mass transport theory,due to a lower water potential in the phloem what does this cause to happen
osmosis from the xylem into the phloem
phloem loading (at source)
in the mass transport theory, as osmosis has happened into the cell what does this cause the hydrostatic pressure to do
increase
in the mass transport theory, how do sugars move from companion cells into leaf cells (sinks)
facilitated diffusion and probably active transport
in the mass transport theory, how do sugars move out of the S.T.E into the companion cells
facilitated diffusion and active transport
in the mass transport theory, when the sugars move OUT of the phloem what happens to the water potential
increases
in the mass transport theory, what is the result of the water potential increases in the phloem near the sink
water moves out by osmosis into the xylem
in the mass transport theory, when water moves out of the phloem into the xylem, what decreases
hydrostatic pressure
in the mass transport theory, what is the significance of having a high pressure at the source and low pressure at the sink
creates a gradient, this results in movement as the substances go down the pressure gradient
