Ch. 8 Photosynthesis Notes
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Photosynthesis Light energy is used to make glucose Plant and algae in the protista kingdom This process is a reduction reaction, carbon is gaining electrons from the hydrogen Structure of chloroplast Organelle enclosed by double membrane Grana= layers of membranes called thylakoids, LIGHT DEPENDENT REACTION Stroma= CALVIN CYCLE (light independent reaction) Light and Photosynthetic Pigments Plants reflect green light Photosynthetic pigments absorb light energy Pigments absorb light in the visible spectrum Chlorophyll participates directly in light reactions Accessory pigments o Chlorophyll b Green, absorbs all other colors o Carotenoids Yellow, orange, and red (carrots) o Phycobilins Red (algae, don't receive a lot of light) Light- dependent and light- independent reactions Light dependent: produce energy (ATP) and protons o Occurs in grana, within thylakoids In between thylakoids are light absorbing photosystems which contain... Chlorophyll a, accessory pigments Chlorophyll b, carotenoids Electron transport chains create a proton gradient Water is broken down through photolysis into... Electrons: replaces those lost during light dependent reaction
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Ch.8 Photosynthesis
Transcript of Ch. 8 Photosynthesis Notes
Photosynthesis
Light energy is used to make glucose Plant and algae in the protista kingdom This process is a reduction reaction, carbon is gaining electrons from the hydrogen
Structure of chloroplast
Organelle enclosed by double membrane Grana= layers of membranes called thylakoids, LIGHT DEPENDENT REACTION Stroma= CALVIN CYCLE (light independent reaction)
Light and Photosynthetic Pigments
Plants reflect green light Photosynthetic pigments absorb light energy Pigments absorb light in the visible spectrum Chlorophyll participates directly in light reactions Accessory pigments
o Chlorophyll b Green, absorbs all other colors
o Carotenoids Yellow, orange, and red (carrots)
o Phycobilins Red (algae, don't receive a lot of light)
Light- dependent and light- independent reactions
Light dependent: produce energy (ATP) and protonso Occurs in grana, within thylakoids
In between thylakoids are light absorbing photosystems which contain... Chlorophyll a, accessory pigments Chlorophyll b, carotenoids
Electron transport chains create a proton gradient Water is broken down through photolysis into...
Electrons: replaces those lost during light dependent reaction Protons: pass through ATP synthase channels to the stroma for light
independent reaction Oxygen: released into atmosphere as waste
Light Independent: make sugar (PGAL) o Occurs in stroma, to produce sugar or PGAL
CO2, enters through leaves, combines with protons and electrons to produce sugar
Carbon fixation= incorporation of carbon dioxide into sugar molecules, in Calvin Cycle
Structure of the leaf
o Palisade layer continues tightly packed cells containing chloroplast Majority of photosynthesis occurs here Cells of the spongy mesophyll layer also contain chloroplast and carry out
photosynthesis Are not tightly packed, has air spaces for exchange of gases
Epidermis layer does not do photosynthesis Protects delicate underlying cells Allows light to pass into the leaf
Cuticle made of cutin= waterproof, minimizes excessive water loss Guard cells= control the opening and closing of stomates
Allows exchange of gases with minimum water loss
