Photosynthesis Flashcards
(12 cards)
Photosynthesis (Inputs & Outputs)
Inputs : water, carbon dioxide & sunlight
Outputs : oxygen & sugar
- Sugar is a major source of energy
Photosynthesis consists of…
Converting solar energy into chemical
energy such as sugars & carbohydrates
- Also results in the production of oxygen
Autotroph
Organism that produces its own food for energy
Example Grass using photosynthesis
Photoautotroph
Organism that uses sunlight & carbon to produce food
Example : Plants
Heterotroph
An organism that eats other
organisms to get energy
Example : A toad eating a grasshopper
Leaf Surface Features - Stomata
- Open & close
- Prevent des
- Guard cells
- Open and close to allow CO2 uptake and O2
release - Prevent desiccation when closed
- There are guard cells along the stomata
Leaf Surface Features - Waxy Cuticle
- Filter
- Prevents
- Protects
- Filters UV radiation
- Prevents drying out
- Protects against animals and microbes
Leaf Internal structure - Mesophyll
Is the middle layer of the leave where photosynthesis takes place
- It specifically occurs in the chloroplasts (organelles) of cells
Leaf Internal structure - Chloroplasts
Contain thylakoids that contain
chlorophyll or rather pigment that absorbs light
Solar Energy
- Elec R
- Wavelengths
- Visible lights
- Is electromagnetic radiation
- Has wide range of wavelengths
- Short waves (like gamma rays) carry lots of energy
- Visible light only covers a portion of radiation
- Different wavelengths of visible light can be absorbed by pigments like chlorophyll
Light-dependent Reactions
Electron → proteins via ETC
EG → HI moves
ADP → ATP
Released Electron → NADP to NADPH
- The excited electron gets transferred between proteins via the electron transport chain
- An electrochemical gradient is formed causing hydrogen ions to move through ATP synthase
- This causes ADP to convert to ATP
- The released electron eventually goes to the conversion of NADP+ to NADPH
Calvin Cycle (Process)
S1 : Rubisco → reaction between CO2 & RuBP
S2 : 2 three carbon molecules
S3 : These molecules are converted via reduction reaction
S4 : Last compund (G3P) → glucose fomration
S5 : Cycle occurs 6 times
S6 : G3P → RuBP
3 Steps - Carbon fixation, reduction & regeneration of the starting molecule
To form the carbon backbone of carbohydrates, carbon atoms are taken from CO2
Step 1 : RuBsiCO (enzyme) helps a reaction between CO2 and RuBP (molecule)
Step 2 : Two three-carbon molecules result from this carbon fixation
Step 3 : These three-carbon molecules are converted to another compound via reduction reaction
Step 4 : This last compound (G3P) contributes to glucose formation
Step 5 : Calvin cycle process occurs 6 times–once for each carbon atom in glucose
Step 6 : G3P goes to regenerate RuBP
