changes its shape to open & close the stomata
brings water from roots up to where photosynthesis takes place
takes extra, unneeded glucose & moves it to the sink
CO2 enters & oxygen and water come out through here
made up of phloem & xylem (vascular bundle)
waxy, NON-LIVING layer that waterproofs the leaf & protects plant from drying out
layer of cells produces cuticle on bottom of leaf
spongy layer of mesophyll
has big open air spaces, does some photosynthesis
palisades layer of mesophyll
tightly packed layer of cells where most of photosynthesis takes place
layer of cells that produces cuticle on top of leaf
allows the movement of CO2 up from palisades & allows oxygen to leave the leaf
what does cycling maintain in the enviornment?
4 processes the water cycle involves
evaporation, transpiration, condensation, precipitation
happens when heat changes water from a liquid to a gas
happens when water evaporates from the leaves of plants - depends on the properties of water
what happens as moist air rises?
the process by which water vapor turns into a liquid forming clouds
comes in the form of rain, snow, sleet, hail, or fog & it falls when the water drops become heavy
when water runs down hills & mountains into bodies of water
when water soaks into the soil & collects as groundwater. Helps to build the water table
what determines the amt of water the atmosphere can hold?
temp & air pressure
how does the water cycle help the earth
it prevents large changes in global temperatures
what do the carbon & oxygen cycles use?
they’re interdependent on each other and use respiration to produce oxygen & photosynthesis to produce CO2
what is the oxygen produced in photosynthesis?
a waste product & made from water, not CO2
what are DNA & RNA?
what are carbon & hydrogen?
release O2 into the atmosphere by photosynthesis
who needs oxygen?
all life with a mitochondria absorbs it to use during cellular respiration EXCEPT some prokaryotes
why do living organisms need Carbon?
to create organic molecules / macromolecules
absorb CO2 from the atmosphere during photosynthesis & release CO2 during cellular respiration
intake oxygen when they feed & move it up the food chain
output CO2 during cellular respiration
intake CO2 when they feed on organic matter
return organic molecules to the soil during decomposition
release CO2 into the atmosphere when fossil fuels are burned for energy
4 main carbon reservoirs in BIOSPHERE
Atmosphere - as CO2 gas
Ocean - as dissolved CO2 gas
Land - in organisms, rocks, soil
Underground - as coal & fossil fuels & calcium carbonate in rocks
Where does CO2 in atmosphere come from?
-human activity (burning fossil fuels)
how do plants absorb water
through their roots, using capillary action & evaporation to move water to the leaves
what is transpiration aka?
what does high humidity do to transpiration & why?
slows down transpiration because it slows the movement of water to roots
what does increased light do?
increases photosynthesis, increasing transpiration
what happens during droughts?
the stoma close so transpiration stops, making photosynthesis stop or slow
absorption occurs at the…
cohesion & adhesion happens in the…
transpiration takes place in the…
stoma of the leaves
explain process of water movement in plants
water is absorbed through the roots and brought up to the leaves through capillary action
exits through transpiration in the stoma of the leaves