Transcript Document

Regents Biology
2006-2007
Photosynthesis:
Life from Light and Air
Regents Biology
2006-2007
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

Regents Biology
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
sun
ATP
sugars
Regents Biology
Building plants from sunlight & air
 Photosynthesis
2 separate processes
sun
 ENERGY building reactions

 collect sun energy
 use it to make ATP

ATP
SUGAR building reactions
 take the ATP energy
 collect CO2 from air &
H2O from ground
 use all to build sugars
carbon dioxide
water
+ HO
CO
Regents Biology
2
2
H2O
+
CO2
sugars
C6H12O6
sugars
Using light & air to grow plants
 Photosynthesis
using sun’s energy to make ATP
 using CO2 & water to make sugar
 in chloroplasts
 allows plants to grow
 makes a waste product

 oxygen (O2)
(ATP) = used to build the sugar
carbon
sun
+ water + energy  glucose + oxygen
dioxide
6CO2 + 6H2O + sun  C6H12O6 + 6O2
energy
Regents Biology
What do plants need to grow?
 The “factory” for making
energy & sugars

sun
chloroplast
 Fuels
CO2
sunlight
 carbon dioxide
 water
Make ATP!
Make sugar!
I can do it all…
And no one
even notices!

 The Helpers

enzymes
Regents Biology
H2O
ATP
enzymes
sugars
Photosynthesis
sun
ENERGY
building
reactions
ATP
ADP
SUGAR
building
reactions
H2O
Regents Biology
CO2
used immediately
to synthesize sugars
sugar
Chloroplasts are only in plants
animal cells
plant cells
Regents Biology
Chloroplasts
Leaf
absorb
sunlight & CO2
Leaves
sun
CO2
Chloroplasts
in cell
Chloroplast
Chloroplasts
contain
Chlorophyll
Regents Biology
Chloroplast
make
ENERGY & SUGAR
So what does a plant need?
 Bring In
light
 CO2
 H2O

leaves
 Let Out

shoot
O2
 Move Around

sugars
roots
6CO2 + 6H2O + light  C6H12O6 + 6O2
Regents Biology
energy
Leaf Structure
cuticle
epidermis
vascular bundle (vein)
xylem (water)
phloem (sugar)
palisades
layer
spongy
layer
epidermis
cuticle
Regents Biology
stomate
guard
cells
xylem (water)
Transpiration
O2 H O
2
 CO2 in
 O2 out
 water out
 so itBiology
gets
Regents
CO2
stomate
O2 H2O
to leaves from roots
CO2
guard
cells
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
Regents Biology
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
Regents Biology
Stomates & Guard Cells
 Function of stomates



CO2 in
O2 out
H2O out
 gets to leaves for photosynthesis
 Function of guard cells

open & close stomates
guard cell
stomate
Regents Biology
Guard cells & Homeostasis
 Homeostasis

keeping the internal
environment of the
plant balanced
 Stomates open

let CO2 in
 needed to make sugar

let H2O out
 so it gets to leaves

let O2 out
 get rid of waste product
 Stomates close

if too much H2O evaporating
Regents Biology
Xylem
carry water up from roots
Regents Biology
Phloem: food-conducting cells
Regents Biology
 carry sugars around the plant
wherever they are needed
 new leaves
 fruit & seeds
 roots
How are they connected?
Respiration
glucose + oxygen  carbon + water + energy
dioxide
C6H12O6 +
6O2
 6CO2 + 6H2O + ATP
Photosynthesis
carbon
sun
+ water + energy  glucose + oxygen
dioxide
6CO2 + 6H2O + light  C6H12O6 + 6O2
energy
Regents Biology
Energy cycle
sun
Photosynthesis
plants
CO2
glucose
H2O
sugars
animals, plants
Cellular Respiration
The Great Circle
of Life!
Regents Biology Mufasa?
ATP
O2
Another view…
capture
light energy
sun
Photosynthesis
synthesis
producers, autotrophs
CO2
waste
organic
O2
molecules waste
H2O
waste
food
consumers, heterotrophs
digestion
Cellular Respiration
Regents Biology
release
chemical energy
ATP
The poetic perspective
 All of the solid material of every plant
was built out of thin air
 All of the solid material of every animal
was built from plant material
air
Regents Biology
Then all the cats, dogs,
mice, people & elephants…
are really strands of air woven
together by sunlight!
sun
Got the energy…
Ask Questions!!
Regents Biology
2006-2007
Ghosts of Lectures Past
(storage)
Regents Biology
2006-2007
Putting it all together
 Making a living…

sunlight
 leaves = solar collectors
 photosynthesis

gases: CO2 in & O2 out
 stomates = gases in & out

H2O
 roots take in water from soil
 pulled up by leaf evaporation

nutrients
 roots take in from soil
Regents Biology