Autotrophs
-use light energy to create their own food during the process called photosynthesis
All food chains and energy production begins with. . .
-the sun
Chloroplasts
-convert light energy into glucose molecules
Glucose
-a carb that is used to give energy
-stores 90x more energy
Heterotrophs
-obtain energy from the foods they eat
Mitochondria
-used to convert glucose into ATP (cellular respiration)
Chloroplasts vs. Mitochondria
-chloroplasts are only in plants
-mitochondria are found in all eukarya
ATP
-stands for Adenosine Triphosphate
-has 3 phosphate bonds
-one phosphate breaks off = energy is released
-can be recharged
-stores small amount of energy
ADP
-stands for Adenosine Diphosphate
-after the broken bond released energy, energy from the sun or food can add a phosphate back to recharge
Equation of photosynthesis
6CO2 + 6H2O + sunlight------> C6H12O6 + 6O2
Van Helmont
-Do plants gain mass from soil or water?
-Result: plant gained 164 pounds, soil mass stayed the same
-Conclusion: The mass comes from water, not the soil
Priestley
-Do plants release a necessary gas into the air?
-Result: mouse w/o plant died and candle w/o plant went out---> mouse w/ plant stayed alive, candle with plant stayed lit
-Conclusion: plants release oxygen into the air
Ingenhousz
-Do plants require light to give off oxygen?
-Result: only the candle with the plant subjected to light stayed lit
-Conclusion: plants only produce oxygen in the presence of light
Plants bring in. . .
-light
-CO2
-H2O
Plants let out. . .
-O2
Plants move around. . .
-sugars
Leaf Structure
Cuticle
-waxy coating that reduces water loss
Epidermis
-skin protecting leaf tissues
Palisades Layer
-high concentration of chloroplasts
-collecting sun's energy
Spongy Layer
-air spaces
-allow for gas exchange
Function of Stomates
-CO2 in
-O2 out
-H2O out
Function of Guard Cells
-open and close stomates
Xylem
-tubes that carry water up from the roots
Phloem
-carry sugar around the plant where ever they are needed
Pigments
-light absorbing molecule
Chlorophyll
-primary light-absorbing pigment
-found inside chloroplasts
Stroma
-fluid surrounding thylakoids
Thylakoids
-flattened membrane disks
Granum
-stack of thylakoids
Light-Dependent Reactions
-takes place in thylakoids
-light energy is converted into chemical energy
Calvin Cycle
-carbon dioxide is "fixed" into sugar using the energy from the light reactions
Light Reactions Equation
-Reactants: light, water, HADP+, ADP(+p)
-Products: NADPH, ATP, and O2
Calvin Cycle Equation
-Reactants: NADPH, ATP, CO2
-Products: glucose, ADP, NADP+
Which is better green or red light?
-Red light = absorbs light
-Green light = reflects light