F215 - Revision thread 13th June 2011

the insulin gene in the plasmid breaks the tetracycline resistance, so this means that the bacteria that takes up this plasmid will not grow on tetracycline as it is not resistant to it! so it will only grow on ampicillin, therefore we only want this bacteria

Reverse transcriptase is used to produce mRNA from DNA. So, it does the opposite of transcription. Its used in genetic engineering, when an mRNA strand for a gene has been isolate (e.g. insulin) then, it is possible to produce the corresponding DNA for insertion into a plasmid

Bacterial conjugation is the transfer of genetic material between bacterial cells by direct cell-to-cell contact or by a bridge-like connection between two cells. it allows them to exchange genes for resistance. ect.

For sympatric speciation, you need distruptive selection to occur. I saw a legacy exam question where they had seahorses who were either big or small. They were undergoing distruptive selection and had formed seperate species in the same area. If a big seahorse and small seahorse had medium sized offspring, the medium sized offspring had a selective disadvantage. So the population eventually seperated so much into big and small that there was very little exchange of alleles. Therefore speciation had occured as they were no longer able to produce fertile offspring

biotic environmental pressures:
Competition - Interspecific and intraspecific
Availability of prey to eat
Diseases or infecting bacteria
Parasites

abiotic pressures:
Temperature
Water availability
Nitrates in the soil
Wind
Light

do we need to know about troponin and f actin?

is this correct?
hydrolysis of ATP = breaks crossbridge?

Reverse transcriptase is used to produce mRNA from DNA. So, it does the opposite of transcription. Its used in genetic engineering, when an mRNA strand for a gene has been isolate (e.g. insulin) then, it is possible to produce the corresponding DNA for insertion into a plasmid

Bacterial conjugation is the transfer of genetic material between bacterial cells by direct cell-to-cell contact or by a bridge-like connection between two cells. it allows them to exchange genes for resistance. ect.

do we need to know about troponin and f actin?

Reverse transcriptase is used to produce mRNA from DNA. So, it does the opposite of transcription. Its used in genetic engineering, when an mRNA strand for a gene has been isolate (e.g. insulin) then, it is possible to produce the corresponding DNA for insertion into a plasmid

Bacterial conjugation is the transfer of genetic material between bacterial cells by direct cell-to-cell contact or by a bridge-like connection between two cells. it allows them to exchange genes for resistance. ect.

1. Lac Operon
2. Apoptosis
3. Chi squared test
4. Hardy Weinberg Equations
5. Differences and similaries between natural and artificial selection
6. Genetic Drift
7. Advantages disadvantages of plant cloning
8. Immobilisation of enzymes
9. Electrophoresis
10. PCR
11. The Brain, structure and so on
12. Dopamine and the DRD4 receptor.

May be wrong tho man, but yeah hope that helps.

doesn't it produce a single strand of DNA (cDNA) from mRNA? sorry just worried now aha

thankks

is there any reason why we break the tetracycline resistance and not the ampicillin?

I don't think you'll need to know bacterial conjugation but reverse transcriptase is used to produce a DNA strand in the host cell. It basically takes RNA and changes it to DNA.

Thats right, it does make the single strand of cDNA. The single strand can be made double by DNA transcriptase. Sorry for making it a bit unclear

yes because the binding site for the insulin gene is bang in the middle of the tetracycline resistant gene ! not the ampicillin. so ampicillin resitance remains

Crossing over in prophase 1 would give different allele combinations e.g could have a bit of chrosome 2 swapped with another bit of chromosome 2.

Random assortment of bivalents/chrosomosomes during metaphase 1

Random assortment of chromatids during metaphase 1

Fertilization is random too.

Even interphase, DNA replication - can go wrong and produce variation > but it's a bit too much i think