UVIC BIO 150 Final Exam 1
Questions And 100% Correct Answers
Top Rated
what part of roots controls solute uptake?
The plasma membranes
what must solutes move through to reach the water conducting xylem
tissue at the center of the root
must move through root epidermis & cortex
- this process involves passage across plasma membranes of root cells
plasma membranes are
selectively permeable, allowing entry of needed minerals and keeping
out unneeded or toxic substances
two possible routes to a plants xylem
1) intracellular
2) Extracellular
intracellular route to xylem is when...
water & solutes cross plasma membrane of root hair, travel through
passages (plasmodesmata) between cells to xylem
the extacellular route to xylem is when...
solution moves within cell walls and extracellular spaces; does not cross
any plasma membranes until it hits the Casparian strip
,What is the Casparian Strip and what does it do
- a continuous waxy barrier that stops water and solutes from entering
the xylem through cell walls
- forces water & solutes to cross a plasma membrane into an
endodermal cell (the ring of cells around a vascular bundle)
- this plasma membrane regulates mineral uptake for the the
intercellular route.
what pulls water up xylem vessels
Transcription
what is Xylem sap composed of
water & minerals transported in xylem vessels
what acquires nutrients from air water and soil
plants
what is 96% of plants' dry weight?
- organic carbon-containing compounds
What is root pressure?
- when roots exert slight upward force on xylem sap by actively
pumping minerals into the xylem; water follows by osmosis
- Root pressure is enough force xylem sap up a few meters
what is transpiration in relation to xylems
•-Transpiration is the loss of water from leaves •
, - (1) Water exit leaves through stomata (singular stoma)
- then Water diffuses out of open stoma because outside air is usually
drier than inside leaf. •
- which then creates a vacuum inside leaf.
- requires no energy from the tree
Is water cohesive or adhesive?
both.
cohesive: because of hydrogen bonding which causes molecules to stick
together
adhesive: because it sticks to other surfaces
what within the xylem forms continuous strings from leaves to roots?
Cohering water molecules
what allows water to be sucked up towards the leaves?
both the vacuum created by water loss in leaves and the cohesion of
water
whats does adhesions aid with in the xylem
helps counteract the downward pull of gravity in xylem walls
What do guard cells do?
- control transpiration
- since during dry conditions plants must retain water meaning they
Questions And 100% Correct Answers
Top Rated
what part of roots controls solute uptake?
The plasma membranes
what must solutes move through to reach the water conducting xylem
tissue at the center of the root
must move through root epidermis & cortex
- this process involves passage across plasma membranes of root cells
plasma membranes are
selectively permeable, allowing entry of needed minerals and keeping
out unneeded or toxic substances
two possible routes to a plants xylem
1) intracellular
2) Extracellular
intracellular route to xylem is when...
water & solutes cross plasma membrane of root hair, travel through
passages (plasmodesmata) between cells to xylem
the extacellular route to xylem is when...
solution moves within cell walls and extracellular spaces; does not cross
any plasma membranes until it hits the Casparian strip
,What is the Casparian Strip and what does it do
- a continuous waxy barrier that stops water and solutes from entering
the xylem through cell walls
- forces water & solutes to cross a plasma membrane into an
endodermal cell (the ring of cells around a vascular bundle)
- this plasma membrane regulates mineral uptake for the the
intercellular route.
what pulls water up xylem vessels
Transcription
what is Xylem sap composed of
water & minerals transported in xylem vessels
what acquires nutrients from air water and soil
plants
what is 96% of plants' dry weight?
- organic carbon-containing compounds
What is root pressure?
- when roots exert slight upward force on xylem sap by actively
pumping minerals into the xylem; water follows by osmosis
- Root pressure is enough force xylem sap up a few meters
what is transpiration in relation to xylems
•-Transpiration is the loss of water from leaves •
, - (1) Water exit leaves through stomata (singular stoma)
- then Water diffuses out of open stoma because outside air is usually
drier than inside leaf. •
- which then creates a vacuum inside leaf.
- requires no energy from the tree
Is water cohesive or adhesive?
both.
cohesive: because of hydrogen bonding which causes molecules to stick
together
adhesive: because it sticks to other surfaces
what within the xylem forms continuous strings from leaves to roots?
Cohering water molecules
what allows water to be sucked up towards the leaves?
both the vacuum created by water loss in leaves and the cohesion of
water
whats does adhesions aid with in the xylem
helps counteract the downward pull of gravity in xylem walls
What do guard cells do?
- control transpiration
- since during dry conditions plants must retain water meaning they
