Importance of constant core temperature in mammals
Mammals are hot-blooded and so they don't receive their energy from the sun
Enzymes work at an optical temperature
Explanation of action of brown adipose tissue raising core temperature
This sends heat to the insulation layers increasing core temperature
When temperature drops below core the rat must be respiring
Adipose tissue acts as an insulator and increases the diffusion pathway
Electrical activity in neurones increases.
This suggests that synapses are being sent to the rat's thermoregulatory centre.
Hot skin is picked up by skin receptors
Comments on data about behaviour of herbivores
There is an overlap between wildebeest and impala
The impala is the herbicide that spent more time in the area with many predators
Less time feeding so less time respiring
Less energy to grow ATP
Herbivores eat crops which reduces agricultural productivity
Heterozygous mice
They have half the allele to the normal mice
Explanation of plants transformed by recombinant DNA technology synthesising an insect protein
Because the genetic code is universal, all organisms and species are
able to insert triplet sequences into the DNA of another
Proteins are made from specific amino acids in groups of three called codons. These amino acids are universal
The inserted gene is not seen as a foreign antigen
The DNA code is degenerate - all base pairs are the same in all organisms
The plant is now producing proteins that contain the desired gene from the insect
Control of heart rate
Barrow receptors detect changes in pressure
DNA probes explained
This enabled them to see visually which probe attached
Reason for using a type of microscope
This gives intense zooming abilities
It uses correct wavelength to see
Em can see inside cells
Calculation of percentage of mitochondria with unusual structure
By counting the unusual mitochondria then diving by the total
Count the number of normal ones and unusual ones in a cell and divide by each other