Unit 6 - Plant Nutrition Flashcards
photosynthesis, leaf structure
Photosynthesis definition
The process by which plants synthesise carbohydrates from raw materials using energy from light
Photosynthesis Word equation
carbon dioxide + water -> Glucose + oxygen
(in the presense of chlorophyll and light)
Photosynthesis Symbol equation
6C02 + 6H20 -> C6H12O6 +6O2
what is chlorophyll?
the protein found within chloroplasts that catalyses reactions
Uses of Glucose in plants(5)
- stored in plants as starch
- used in cellulose to build cell walls
- used for respiration
- converted into sucrose and transported through phloem vessels from source to sink
- converted into nectar and used to attract pollinators
leaf adaptions (2)
- large surface area - maxamise eposure to sunlight
- very thin - aid diffusion of O2 and CO2
purpose of guard cells
open and close stomata
purpose of waxy cuticle
allows light to pass through whilst protecting leaf structure
purpose of epidermal cells
offers protection but thin to allow liht through
features of palisade cells (5)
- contain many chloroplasts
- packed tightly together
- maxamises surface area
- large vacuole pushes chloroplasts to edge of cell
- thin cell walla aid gaseous exchange
features of spongey mesophyll (4)
- irregular shape
- fewer chlorplasts
- smaller than plaisade cells
- spaced out with air pockets in between
Limiting factor definition
something that is in short supply that restricts a process.
Main limiting factors of photosynthesis (3)
- light density
- carbon dioxide concentration
- temperature
(also still limited by amount of chlorophyll)
effect of light intenisty on photosynthesis
- increases with light intensity
- when increased to a certain point photosynthesis cant go any faster as it is no longer the limiting factor
effect of co2 concentration on photosynthesis
- increasing co2 increases photosynthesis
- is a maz rate bc smth new become slimiting
effect of temperature on photosynthesis
- too much heat damages enzymes and causes them to denature
- too much heat also evaporates water out of leaves and forces stomata to close
- too little heat can reduce enzymes reaction rate by reducing number of collisions between actie site and substrate
what is Mg required for in plants ? signs of defficency
- required for chlorophyll
- yellowing between veins of leaves due to lack of chlorophyll production
What is nitrate needed for in plants? signs of defficency
where do plants get nitrate?
- needed for proteins
- stunted growth
- leaves near tips turn yellow
- get from soil
ratio of photosynthesis to respiration
- changes over the day cycle
- constantly respiring and releasing co2
- only photo during the day when sunlight is available
Net Co2 intake during day vs night
day : photo faster than respire resulting in net co2 intake
night : respire more than phto resulting in net release of co2
What is hydrogen carbonate indicator?
a ph indicator that changes colour depending on ph of the solution.
Is CO2 acidic or basic ?
acidic
what ph color is CO2 at atmosepheric level ?
red