Ch8 Photosynthesis Flashcards
Photosynthesis Word equation
Carbon dioxide + water -> glucose + oxygen
Symbol equation
6CO2 + 6H2O -> 6O2 + C6H12O6
photosynthesis
endothermic reaction
energy is transferred from the environment to the chloroplasts by light
Leaf adaptations
leaves are broad- big SA for light to fall on
leaves are thin-short diffusion distances
have veins
have air spaces- allow diffusion
guard cells open and close the stomata to regulate gas exchange
Limiting factors for rate of photosynthesis
- light intensity
- temperature
- CO2 concentration
- amount of chlorophyll
Uses of glucose in plants
- respiration
- energy storage
- protein synthesis
- making lipids
- strengthening cell walls
energy storage
glucose converted into starch
stored in the cells of leaves, tubers or bulbs
lipids are are used as energy storage in seeds
epidermal tissue
secrete waxy substance that waterproofs and protects the surface of the leaf
transparent to let light through
Palisade mesophyll
contains lots of chloroplasts, which carry out photosynthesis
arranged closely together
Spongy mesophyll
contains some chloroplasts for photosynthesis
has big air spaces and a large SA to make the diffusion of gases easier
Stomata
control water lost by transpiration
allow gas exchange
Guard cells
control size of stomata
can be turgid or flaccid
Greenhouse advantages
Turnover is fast so high profits Crops can grow where land is poor Less staff are needed Seed harvest is shot Crops are clean so no need to plough or prepare Final crop is larger and cleaner Can manipulate environmental factors
Greenhouse disadvantages
expensive monitoring equipment and computers
increased outcome has to be balanced against cost of the system
