2010 Jan Unit 4 Flashcards
A large size results in animal being adapted for breeding in colder conditions
Small surface area to volume ratio-more fat
Lose less heat-Insulation
When they are sitting on eggs
Explain how natural selection has accounted for the effect of —on the percentage of —-
Better camouflaged
Resulting in greater survival and reproductive sucess
The percentage of —- changed over a period of time. Use knowledge of climate change to suggest an explanation
Decrease in the coloured animal is not camouflaged/at disadvantage
Non coloured at an advantage
Symmetrical graph. What type of natural selection is it. Evidence of this
Stablising
Few animals survive at the extremes
What is meant by population
All organism of one species in a habitat at a particular time
Describe how you would place the quadrats at random
Generate random numbers by drawing some from a hat
Use the numbers as coordinates to find where to position each quadrat
Describe how you would decide the number of quadrats to use in order to collect
representative data.
Calculate running mean
When enough quadrats this shows little change
Enough to carry out a statistical test
A large number to make sure results are reliable
Statistically signifcant
So not due to chance
One step in which carbon dioxide is produced
Krebs Cycle/ Link reaction/ Pyruvate to Acetlycoenzyme A
Explain how
a decrease in temperature would affect the rate of carbon dioxide production.
Anaerobic respiration
Respiratory reactions controlled by enzymes Rate decreases Less kinetic energy Fewer collisions Fewer E-S substrates
Pyruvic acid to Ethanol
Use this pathway to explain the part played by reduced NAD
Required H/e-/is reduction
NAD reduces Pyruvate
The rate of carbon dioxide production was higher when the apple slices were in
nitrogen than when they were in the air. Explain why.
Respiring anarobically
Anaerobic respiration produces less ATP
More anaerobic respiration to produce same amount of ATP therefore more CO2
Species X has a high rate of photosynthesis at high light intensities,. Species X is the first tree to become established in the succession Explain why?
Vegetation consists mainly of low growing species
few tress;
Species X has high rate of photosynthesis at high light intensity;
Species X grow fastest at high rate of photosynthesis at high light intensities;
Will outcompete other species Y/Z
Species X has a high rate of photosynthesis at high light intensities. Graph Z is lower than X. Species X may change the environment so that it becomes more suitable for species Z.
Use the graph to explain why.
Produces shade/reduces light intensity;
Species Z grows best/photosynthesis best/ in low light intensity /
Species Z does not grow well / low rate of photosynthesis in high
light intensity;
Explain why the biologists selected the hairs at random.
Avoids bias/allows statistical tests to be carried out;
Explain why it was important to check the repeatability of the measurements.
Increases the reliability of the measurements;
If measurements are repeatable, differences less likely to be due
to measurement/personal error/ anomalies unlikely;
Explain why a statistical test was necessary in analysing the results
(A statistical test) determines the probability of results being due to chance
Enables null hypothesis/description of null hypothesis to beaccepted/rejected;
Determines whether correlation/result is significant;
Describe how and explain why the efficiency of energy transfer is different at different
stages in the transfer.
Some light energy fails to strike/is reflected/not of
appropriate wavelength;
Efficiency of photosynthesis in plants is low
Respiratory loss / excretion / faeces /
Loss as heat;
Efficiency of transfer approximately 10%;
Efficiency lower in older animals/herbivores/ primary
consumers
Carnivores use more of their food than herbivores;
Explain how the intensive rearing of domestic livestock increases net productivity
Slaughtered when still growing/before maturity/while young so more energy transferred to biomass
Fed on concentrate controlled diet so higher proportion of (digested) food absorbed
Movement restricted so less respiratory loss/less energy used
Kept inside/so less heat loss / no predators
Genetically selected for high productivity
