On the Wild Side Flashcards
Describe abiotic factors.
Physical or chemical factors: Solar energy input Climate Topography (altitude, slope, aspect, drainage) Oxygen concentration Edaphic (soil pH and mineral content) Pollution Catastrophes.
Describe biotic factors.
Living factors: Competition Grazing Predation Disease Parasitism Mutualism.
These factors are density dependent.
Describe anthropogenic factors.
Human activity.
Describe primary succession.
Colonisation is led by a pioneer species.
The environment becomes altered when the pioneer species die and change the abiotic environment through releasing nutrients into the soil.
The final species is the climax community.
Secondary succession.
Occurs in areas where a disturbance has removed most or all of the species living in the previous ecological community but has left behind rich soil.
Some species may remain and recolonise after the disturbance
Define gross primary productivity.
The rate at which energy is incorporated into organic molecules.
Define autotrophs.
Organisms that can make their own organic compounds from inorganic compounds.
Define net primary productivity.
The rate at which energy is transferred into the organic molecules making up cell biomass.
What is the calculation for net primary productivity?
Net primary productivity = gross primary productivity minus respiration.
Describe light-dependent photosynthesis.
Occurs in the thylakoid membrane.
Light energy excites electrons in the chlorophyll
Electron from PSll travels down the electron transport chain via a series of redox reactions.
Energy is used to synthesis ATP in photophosphorylation.
Electrons from PSII replace those from PSI.
Photolysis occurs, producing oxygen gas, H+ ions and electrons.
The electrons from PSl and the hydrogen ions combine with NADP to form reduced NADP.
Describe light-independent photosynthesis.
1) Carbon dioxide diffuses into the stroma of the chloroplast.
2) The CO2 combines with a 5-carbon compound: Ribulose bisphosphate (RuBP). This reaction is catalysed by the enzyme ribulose bisphosphate carboxylase (RuBISCO).
3) The 6- carbon compound formed is unstable and immediately breaks down into 2 3-carbon molecules : glycerate 3-phosphate (GP).
4) This 3-carbon compound is reduced to form a 3-carbon sugar phosphate: glyceraldehyde-3-phosphate (GALP). The hydrogen for the reduction comes from the reduced NADP from the light-dependent reactions. ATP from the light-dependent reactions provides the energy required for this endothermic reaction.
5) ⅚ of the GALP is involved in the recreation of RuBP. The molecules rearrange to form 5- carbon compounds which are then phosphorylated using ATP to form RuBP.
6) ⅙ of the GALP is involved in the formation of glucose which can then be used to make other materials that the plant needs like scratch, sucrose and cellulose.
Describe primary consumers.
Herbivores. Heterotrophs that eat plant material.
Describe secondary consumers.
Carnivores. Eat primary consumers.
Describe tertiary consumers.
Eat other consumers.
Describe detritivores.
Primary consumers that feed on dead organic materials (detritus).
Describe peat bogs.
Anaerobic and acidic.
Plants all have different types of pollen. Pollen grains have a tough outer layer that is decay resistant. Peat forms in layers. Each plant has specific conditions.
Describe dendrochronology.
Trees grow new layers of xylem vessels. New vessels grow in accordance to season. Wide vessels in spring, narrow vessels in summer.
Describe DNA hybridisation.
When DNA is heated, base pairs break. We can mix it to make a hybrid. Not all bases complementary base pairs. Hybrid DNA denatures at lower temperatures.
Define profile sequencing.
Compares sequence of bases in different species. Fewer differences are more common ancestors.
Describe molecular clocks.
Molecular change in DNA over time can be used. Evolutionary trees can be formed.
Describe profiling.
Restriction enzymes cut at specific sequences. Produces fragments that can be visualised in bands. If there are mutations, restriction enzymes will not cut DNA.
Define allopatric speciation.
Geographical isolation.
Define sympatric speciation.
Reproductive isolation.
Describe ecological speciation.
Live in different parts of the habitat.
Describe temporal speciation.
Reproduce at different times.
Describe behavioural speciation.
Do not respond to mating behaviour.
Describe physical incompatibility.
Physical issues with reproduction.
Describe hybrid inviability.
Do not survive long enough to reproduce.
Describe hybrid sterility.
Cannot reproduce.
Describe the carbon cycle.
Release: Combustion Deforestation Volcanic activity Sedimentation Increase in acid rain.
Remove:
Sustainable resources.
Reforestation.
Ecosystem
All organisms living in one particular area and all the non-living factors together
Habitat
The place where an organism lives
Population
All the organisms of one species in a habitat
Population size
The number of individuals of one species in a particular area
Community
The populations of different species in a habitat
Abundance
The number is one species in a particular area
Distribution
Where a species is within a particular area
Competition
Occurs when two or more individuals strive to obtain the same resources when these are in short supply
Inter specific competition
Organisms of different species compete for the same resources
Intraspecific
Organum of the same species compete with each other for the same resources
Carrying capacity
Maximum stable population size of a species that an ecosystem can support
Predator/prey relationship
Predator population will fall or grow a little after the prey population
Niche
It’s role in the habitat, no two species can occupy the same niche
Succession
The sequences of changes in a community over a period of time
Climax Community
The final stage of succession, where the community is stable and there is one or two dominant species.
Where does light-independent take place?
Stroma
Chemiosmosis
Where the ions flow through a ATP synthase from the thylakoid space into the stroma
Observing patterns by ecological sampling.
Line transect. Tape measure laid along several zones to look at. Quadrats used to record data at regular intervals.
Effect of temperature on hatching success of brine shrimp.
Test at a range of temperatures. Place sea salt into a 100cm3 beaker. Add 100cm3 of dechlorinated water and stir until salt dissolves. Place a pinch of eggs onto a large sheet of paper. Wet the paper. Dab the paper onto the white sheet to pick up eggs. Put the paper into the beaker. Use forceps to remove the paper.
