Outer membrane (Chloroplast envelope)- keeps all things needed for photosynthesis close
Lamella- holds thylakoid membranes together
Grana- stacks of thylakoid membranes
Stroma- site of light independent reactions (calvin cycle)
Thylakoid membranes- site of light dependent reactions, large surface area and lots of atp synthase
ADP + Pi = ATP photophosphorylation
enzyme; atp synthase
ATP = ADP + Pi hydrolysis
6CO2 + 6CO2 = 6O2 + C6H12O6
Dependent Independent Dependent Independent
Happens in the thylakoid membranes- chlorophyl and electron transport molecules embedded in the membrane
1. electrons in chlorophyl become excited due to light energy hitting the chlorophyl
2. move along into the electron transport chain, oxidation and reduction changes electrons
3. this causes the photophosporylation of ADP and Pi to form ATP
4. water is split by photolysis to form, H+ ions, electrons and oxygen
5. the electrons are used to replace ones in the chlorophyl, H+ is used to reduce nadp to produce reduced nadp, oxygen is a waste product
This happens in the stroma
1. Carbon dioxide combines with RuBP to form a 6 carbon compound, however this is unstable and it splits into two 3 carbon compounds called GP. Rubisco acts as the catalyst in this reaction.
2. GP is reduced to GALP, this requires energy from ATP, the energy is in the phosphate bond, so this break into ADP and Pi. It also requires H+ ions from reduced nadp, this is converted back to nadp.
3. 12 GALP molecules are made in total, 2 GALPS are used to make Glucose, 10 GALP are therefore used to regenerate RuBP, this also requires energy from ATP.
4. The cycle continues
Gross primary productivity (GPP)- rate at which energy is transferred to organic material
Net primary productivity (NPP)- rate at which energy is transferred to biomass
NPP = GPP - R (respiration)
. Leaf; pass through, absorbed, evaporates or reflected
. Not correct wavelength
. Not all of plant eaten
. Metabolic reactions; respiration, movement
. Hit incorrect part of plant
The number of a certain species in relation to their habitat, this includes conditions such as abiotic, biotic and anthropogenic.
Solar conditions (light intensity/hours of light)
Topography (height of land)
Where a certain number of organisms are in terms of their location in accordance to other organisms of the same or different species.
Primary Succession- newly formed habitat on not previously colonised land
Secondary Succession- succession on a previously colonised area of land
Deflected Succession- succession maintained by human interference
Succession On A Sand Dune
1. Pioneer species- colonised new land with poor nutrient content, they break up the soil forming the start of soil. Xerophytic adaptations, minimising water loss helps them survive.
2. Couch grass- build dunes, use long roots to trap sand, grow best when buried.
3. Marram grass- resist water loss (stomata present on inside).
4. Variety of plant species- conditions become more favourable, nitrogen fixers improve content level of soil.
5. Climax community- eventually trees are present, they are much more dominant than smaller plants. There is a balance of interactions between plants and animals.
Formation of two new species from an original single species, due to changes in environmental pressures causing reproductive isolation.
Gene pool- total of all allele frequency in a population
Allele frequency- number of different alleles or gene types in a population (gene pool)
habitat- different area
temperate- reproduce at different times
mechanical- organs are incompatable
behavioural- don't respond to each others mating displays
hybrid sterility- offspring cannot reproduce (sterile)
hybrid inviability- offspring don't survive to reproduce
Natural Selection- selective pressure put on a population, certain organisms have adaptations or mutations that mean they can survive, they reproduce and pass on their genes to their offspring. The allele for ones that can survive therefore increases.
Evolution- gradual change in allele frequency over time
1. DNA evidence- evolved from a common ancestor (DNA hybridisation, DNA profiling and DNA molecular clocks)
2. Proteomics- the study of proteins, the closer related the proteins the closer the genetic information is (DNA)
Green House Gases
Methane and carbon dioxide
Absorb infrared radiation reemmited by the earths surface, causes an increase in vibrational energy and this causes a rise in temperature. This is called the Green House Effect. Increased levels causes a negative impact and increase the effects of Global warming & climate change.
Peat bogs- dead organic material from plants (carbon fixation)
Dendrochronology- study of tree rings (wider = temperature hotter and rainfall higher)
Temperature & carbon dioxide records
The Effect Of Global Warming
Enzymes; at high temperatures enzymes become denatured
Very below optimum; an increase in temperature causes an increase in activity
Just below optimum; an increase in temperature causes denaturing and therefore a decrease in activity. This results in slowing and eventually stopping metabolic processes.
Migrate; if the temperature becomes too hot species can move north or vice versa. However if they live very far north in places such as the tundra they risk extinction, they have to adapt to survive.
Alien Species; due to migration alien species can invade habitats of already present organisms, this can pose a threat, the current species will have to adapt to survive.