State 2 processes that occur in the cell during in
DNA replication
protein synthesis
membrane synthesis
transcription/translation
respiration
organelle synthesis
1 of 7
Explain how distinct phenotype differences between
Populations geologically isolated
mutations occur
new alleles arise
no mixing of the popukations
adaptation to location - different selection pressures eg coat colour for camoflage
beneficial alleles increase frequency
ii) suggest why the populations are classed as subspecies rather than different species
they are geographically isolated but are still able to interbreed freely with fertile offspring. they have similar behavioural/biological/biochemical features
2 of 7
State 3 practical precautions that must be taken b
male sterility gene/emasculation
anthers removed before maturity
flowers isolated
pollen transfered by hand
3 of 7
The Chi^2 result was very large. explain the discr
Genes are linked/on same chromasome
no random assortment
large number of parental types
small number of recombinants
crossing over during Metaphase 1
between non-sister chromatids of homologous chromasome
number of recombinants depends on closeness of genes
4 of 7
State the functions of the lac operon
Operator region - length of DNA that switches off/on structural genes
Promoter region - length of DNA where the enzyme RNA polyperase binds to begin transcription of structural genes
Repressor molecule - prevents RNA polyperase binding with promoter
Beta Galactase - breaks down lactose
Lactose Permease - increases uptake of lactose
5 of 7
Explain how Beta Galactosidase and lactose permeas
Regulator gene produced repressor protein
Protein binds to the oerator region
it prevents RNA polyperase binding
so no transcription/translation of genes
saves energy
saves amino acids/resources
6 of 7
Describe the events that occur in E Coli when lact
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