3.3 photosynthesis Flashcards
photosynthesis equation
raw materials
carbon dioxide + water -> light energy -> glucose + oxygen
products
chlorophyll?
chlorophyll is the green pigment found in chloroplasts that is responsible for absorbing light energy from sun converting it into chemical energy
two stages of photosynthesis
light dependant reactions
carbon fixation cycle
stage 1 of photosynthesis
light energy from sun is trapped by chlorophyll in chloroplasts and converted into chemical energy this chemical energy is used to split water into hydrogen ions and ATP and oxygen the oxygen is then realeased as a bi product and diffuses out the cell
two products that is passed on from stage 1 to stage 2
hydrogen ions and ATP
chemicals that controll the reactions of state 2
enzyme as stage 2 is a series of enzyme controlled reactions
stage 2 carbon fixation cycle
series of enzyme controlled reactiin that used hydrogen ions and Atp from stage 1 to convert carbon dioxide into glucose
three chemical energy in glucose produces by photosynthesis
used as a substrate for respiration to produce ATp
converted into cellulose for cell walls
converted into startch for storage
what is a limiting factor
environmental factor that prevents the rate of photosynthesis increasing
three limiting factor
light intensity
temperature
co2 concentrations
impact of factors that limit photosynthesis on plant growth rate
temperature is the limiting factor because temp must be optimum for maximum enzyme activity. if temp is below optimum enzymes will be less active and the photosynthesis reaction will slow down. If temp is above optimum enzyme will denature and photosynthesis reaction will stop completely.
light intensity limit’s photo as light energy is neeed for light reactions
co2 concentration limits photo as co2 is a raw material for carbon fixation in stage 2
less photosynthesis = less glucose produces = less glucose for respiration= less Atp produces by respiration = less energy available for cell division = less plant growth
how to measure photosynthesis measure
aquatic plant such as pondweed thag lives underwater as plant carries out photosynthesis it releases bubbles of oxygen gas as a by profyct by counting number of 02 bubbles released or measuring the volume of 02 gas released in period of time you can measure the rate of photosynthesis (the elodea bubbler experiment)
