C1.3 Photosynthesis Flashcards
photosynthesis
production of glucose from carbon dioxide and water in presence of chlorophyll and enzyme
using light energy and produce oxygen
what happens to glucose
it is temporarily stored and then used for metabolic activities
photosynthesis formula
6co2 + 6H2O + light energy -> c6h12o6 + 6o2
wider significance of photosynthesis
maintains composition of atmosphere
some oxygen converted into ozone in upper atmosphere
what is light
form of electromagnetic radiation produced by sun
white light from spectrum - all colours which appear white
pigments
coloured compounds produced by metabolism
accessory pigments
light absorbing compounds that trap light energy and channel it to chlorophyll, which initiates photosynthesis
biological pigments
coloured and produced by metabolism
examples of biological pigments
chlorophyll
what colour is reflected by plants
green which is why it is visible
orange and yellow as well but not as much
what colour is absorbed by plants
red and blue
how does Co2 get converted to glucose
- light energy being used to split water
- glucose being built of from co2
photolysis
splitting of water molecules using light energy
features of cyanobacteria
first organism to produce oxygen
contain photosynthetic pigments
have accessory pigments
chlorophyll and phycobilins
2 organisms to produce oxygen as a by product
red/green algae and cyanobacteria
red algae features in photosynthesis
have same pigments as cyanobacteria
get most their colour from phycoerythrin
green and red algae features in photosynthesis
contains chloroplasts a and b which give them bright green colours
have accessory pigments which give red-orange and yellow colours
chromatography
used to separate components of a mixture
involves letting soluble substances spread across filter paper
what is chromatography used for
separation and identification of pigments in a mixture
separating biologically active molecules
easy steps of chromatography
- leaves boiled
- grinded with sand
- propane added as solvent
- centrifuged
- solution created and stored
chromatograms
patterns formed on an absorbent medium showing the result of separating the components of a mixture by chromatography
what are chromatograms typically run on
adsorbent paper, powdered solid or thin film of dried solid
features and steps of paper chromatography
liquid adsorbed om to the surface
papers pores adsorb and form molecules with water - stationary phase
pigments more soluble in solvent that water move rapidly up the paper
Thin layer chromatography (TLC)
stationary phase of silica or alumina particles bonded to a thin layer of glass or plastic
separates a mixture of pigments based on how strongly they are adsorbed on stationary phase and dissolve in mobile phase
mobile phase
liquid or mixture of liquids
Rf Value
distance moved by substance / distance moved by solvent
what does the Rf value depend on
compounds, solvent, temperature and other factors like nature of TLC plate
absorption spectrum
a graph showing the relative absorbance of different wavelengths of light by a pigment
how is absorption spectra of chlorophyll pigments obtained
by measuring their absorption of V B G Y O R
Action spectrum
range of wavelengths of light within which a process like photosynthesis takes place
what does the action spectrum graph record
amount of photosynthesis occurring at each wavelength
limiting factors of photosynthesis
concentrations of CO2
light intensity
temperature
experiment to measure the rate of photosynthesis
root of pondweed bubbling
microburette
used in pondweed experiment to measure volume of oxygen given out in light by tracking of a bubble in capillary tube
machines used in pondweed experiment
microburette
oxygen sensor probe
pH meter
