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DO NOW. Name the stages of cellular respiration and where it occurs Where is the majority of the ATP produced? What is the function of coenzyme A?. Fill in the following. The light reaction makes……….. And …………. Which are used in the Calvin cycle The light reaction occurs in the …………… - PowerPoint PPT PresentationTRANSCRIPT
12Bio 2011
DO NOW Name the stages of cellular respiration
and where it occurs
Where is the majority of the ATP produced?
What is the function of coenzyme A?
12Bio 2011
Fill in the following The light reaction makes……….. And
…………. Which are used in the Calvin cycle
The light reaction occurs in the ……………
The dark reaction occurs in the ……………
12Bio 2011
PHOTOSYNTHESISYear 12 Biology (MAH)
12Bio 2011
What is Photosynthesis? Write everything that you know in
groups of two regarding photosynthesis
Share with the class
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Basis of life? Produces oxygen which all living things
require.
Plants – bottom of the food chain
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What is it? Photosynthesis is the process by which plants
convert LIGHT ENERGY into CHEMICAL ENERGY (compounds which can be used by the plants)
Light is captured by the pigment CHLOROPHYLL, found in the CHLOROPLASTS of leaves and stems of plants
Chlorophyll reflects GREEN light
“The ability of plants to make their own food”
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Chloroplast structure
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Where are they found?
Most chloroplasts are found in the palisade layer which is located close to the top of the leaf. This enables as much sunlight as possible to be absorbed and increases the efficiency of photosynthesis.
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Photosynthesis equation
6CO2 + 6H2O ------ C6H12O6 + 6O2
SUNLIGHT CHLOROPHYLL
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Carbohydrates
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THE STEPS Photosynthesis takes place in two
phases
› Light phase: which occurs in the thylakoids (light dependent)
› Calvin cycle (Dark phase): which occurs in the stroma (light independent)
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Light Reaction Occurs on the grana Light energy is used to do two things
› Excite electrons (give them more energy) to energise electrons along an electron transport chain
› Split water
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Electron Excitation When light strikes an electron in a
chlorophyll molecule, the electrons gain enough energy to be channelled into electron transport chain
Here ATP is produced. As high energy electrons from chlorophyll pass down an electron transport chain they release energy and ATP forms
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Photolysis – splitting of water
Water is split into hydrogen ions electrons and oxygen
Electrons used to replace those used in electron transport chain
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LIGHT PHASE
ENERGY USED TO DO TWO THINGS:› Split water into hydrogen and oxygen
(Hydrogen goes to fill Hydrogen carrier NADP NADPH2
› Some energy is used to charge up ADP ATP
NADPH2 and ATP then move to the stroma for the Calvin Cycle
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Dark Cycle/Calvin Cycle Cycle beings by carbon dioxide being
captured from the air and fixed into a molecule in the stroma
The Calvin cycle then reduces fixed carbon to glucose with the help of NADH2 and ATP from the light phase
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STEPS Carbon dioxide is attached to the five carbon sugar compound
(Ribulose -1-5-biphosphate) by the enzyme Rubisco forming a SIX carbon compound.
The six carbon intermediate compound is UNSTABLE and breaks up into two molecules of PGA (3 Phosphoglycerate)
The PGA molecules are converted to PGAL (3-phosphoglyceraldehyde). This requires ATP and NADPH. The NADPH supplies H atoms and electrons needed for this reaction. The ADP and NADP are then ‘refilled’ by the light phase
The PGAL molecules are converted via a number of steps to glucose, cellulose, starch, disaccharides, lipids and amino acids OR will be recycled through a variety of reactions to form Ribulose-1-5- biphosphate ready to accept another carbon dioxide.
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Compounds plant requires including glucose
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CLOZE Activity In PAIRS fill in the gaps to the
paragraph using the words provided
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Photosynthesis summary
Light dependent:
-
Light independent:
O2
H2O CO2
C6H12O6
Chemical energy (ATP)
Reactive hydrogen(NADPH)
(eventually)
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Photosynthesis summary
Light dependent:
- Grana/thylakoid membranes- Water converted to oxygen- Light energy converted to chemical energy (ATP)
Light independent:
- Chloroplast stroma- Carbon dioxide converted to glucose- Requires chemical energy (ATP)- Requires reactive hydrogen
O2
H2O CO2
C6H12O6
Chemical energy (ATP)
Reactive hydrogen(NADPH)
(eventually)
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Compare/Contrast Compare and contrast photosynthesis
vs respiration› How many major steps?› Inputs› Outputs› Where occurs
› Should take up at least one page in your book (Good for revision)
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Compare and Contrast
PHOTOSYNTHESIS RESPRIRATION
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Comparing photosynthesis and respiration
Photosynthesis Respiration
Both require membranesP.S. – thylakoidResp – inner mitochondrialmembrane
Converts mobilechemical energyto ATP
Converts lightenergy to mobilechemical energy
Occurs in chloroplasts
Occurs in cytoplasmand mitochondria
Both involveATP and reactivehydrogen atoms
Produces O2Consumes H2O
Produces H2OConsumes O2
Both have electrontransport chains
Both involve energyconversion
2 major steps
3 major steps
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What effects photosynthesis?
Enzymes Temperature Amount of carbon dioxide Light intensity and wavelength Chlorophyll and minerals Absorption of carbon dioxide Sufficient water
Use Bayley pg. 137 to describe factors that effect photosynthesis and describe what is the compensation point
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TO DO!! Make a poem/rap about
photosynthesis and combine all knowledge regarding light phase and Calvin cycle
Look at these for inspiration
This will HELP you remember what you have learnt
Prepare to report to class
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RELATIONSHIP BETWEEN PHOTOSYNTHESIS AND RESPIRATION??
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Carbon Dioxide Saturation
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See an animation of Mitosis
Square dance
http://www.cellsalive.com/meiosis.htm