Photosynthesis: Life from Light and Air

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Photosynthesis Life from Light and Air
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Plants are energy producers

• Like animals, plants need energy to live
• unlike animals, plants dont need to eat food to
  make that energy
• Plants make both FOOD ENERGY
• animals are consumers
• plants are producers

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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
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Building plants from sunlight air
sun

• 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

ATP

sugars
carbon dioxide CO2
sugars C6H12O6
water H2O

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Using light air to grow plants

• Photosynthesis
• using suns energy to make ATP
• using CO2 water to make sugar
• in chloroplasts
• allows plants to grow
• makes a waste product
• oxygen (O2)

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What do plants need to grow?

• The factory for making energy sugars
• chloroplast
• Fuels
• sunlight
• carbon dioxide
• water
• The Helpers
• enzymes

Make ATP!Make sugar!I can do it allAnd no
oneeven notices!
sun
ATP
enzymes
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Photosynthesis
sun
ENERGYbuilding reactions
ATP
ADP
SUGARbuilding reactions
used immediatelyto synthesize sugars
sugar
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Chloroplasts are only in plants
animal cells
plant cells
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Chloroplasts
absorbsunlight CO2
Leaf
sun
Leaves
Chloroplastsin cell
Chloroplast
Chloroplast
Chloroplasts contain Chlorophyll
makeENERGY SUGAR
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So what does a plant need?

• Bring In
• light
• CO2
• H2O
• Let Out
• O2
• Move Around
• sugars

leaves
shoot
roots
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Leaf Structure
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Transpiration
O2
H2O
CO2

• CO2 in
• O2 out
• water out
• so it gets to leaves from roots

H2O
CO2
O2
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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

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Function of Leaf Structures

• Cuticle
• waxy coating reduces water loss
• Epidermis
• skin protecting leaf tissues
• Palisades layer
• high concentration of chloroplasts
• collecting suns energy
• photosynthesis
• making ATP sugars
• Spongy layer
• air spaces
• gas exchange
• CO2 in for sugar production, remove waste O2

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Do Now

• What is the equation for photosynthesis?
• Check answers to Tuesday nights homework
• 1. 4 2. 2 3. 4 4. 3 5. 2 6. 2 7. 4
• 8. Two raw materials necessary for photosynthesis
  are carbon dioxide and water. These two molecules
  are broken apart and rearranged to produce
  glucose and oxygen molecules

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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
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Guard cells Homeostasis

• Homeostasis
• keeping the internal environment of the plant
  balanced
• Stomates open
• let CO2 in
• needed to make sugars
• let H2O out
• needed for photosynthesis
• let O2 out
• get rid of waste product
• Stomates close
• if too much H2O evaporating

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Xylem
carry water up from roots
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Phloem food-conducting cells

• carry sugars around the plant wherever they are
  needed
• new leaves
• fruit seeds
• roots

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How are they connected?
Respiration
Photosynthesis
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Energy cycle
Photosynthesis
plants
CO2
O2
animals, plants
Cellular Respiration
ATP
The Great Circleof Life! Mufasa?
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Another view
capturelight energy
Photosynthesis
synthesis
producers, autotrophs
CO2
O2
organicmoleculesfood
waste
waste
waste
consumers, heterotrophs
digestion
Cellular Respiration
ATP
releasechemical energy