18-09-2012, 01:14 PM
Photosynthesis: Life from Light and Air
Photosynthesis.ppt (Size: 4.76 MB / Downloads: 124)
Plants are energy producers
Like animals, plants need energy to live
unlike animals, plants don’t need to eat food to make that energy
Plants make both FOOD & ENERGY
animals are consumers
plants are producers
How do plants make energy & food?
Plants use the energy from the sun
to make ATP energy
to make sugars
glucose, sucrose, cellulose, starch, & more
Building plants from sunlight & air
Photosynthesis
2 separate processes
ENERGY building reactions
collect sun energy
use it to make ATP
SUGAR building reactions
take the ATP energy
collect CO2 from air & H2O from ground
use all to build sugars
Transpiration
Water evaporates from the stomates in the leaves
pulls water up from roots
water molecules stick to each other
more water is pulled up tree from ground
Function of Leaf Structures
Cuticle
waxy coating reduces water loss
Epidermis
skin protecting leaf tissues
Palisades layer
high concentration of chloroplasts
collecting sun’s energy
photosynthesis
making ATP & sugars
Spongy layer
air spaces
gas exchange
CO2 in for sugar production, remove waste O2