Competition - post a photo you've taken of nature >>

OFFICIAL OCR A2 Biology - F215 Thread

Scroll to see replies

hey im new to this but i wanted to ask .. whats the difference between sequencing a genome and genetic engineering?

i would be so greatful if someone could outline the steps of each ! :smile:

Reply 41

Vanita28

genetic engineering obtains a gene which inserts it into another organism and sequencing a genome is finding out which gene is where in the genome to
 show evolutionary relationships between species
 Comparisons between pathogenic and non-pathogenic organisms can find out the gene causing certain diseases- help with drug developments
 Can reveal the presence of mutant alleles or alleles with a risk which cause a disease
 Any changes to the DNA can be monitored if the genome is known

this is an outline of sequencing:
Outline the steps involved in sequencing the genome of an organism
1. Map the genome: this identifies where in the genome each section came from, often done by locating the sections with reference to be known as microsatellites which exist on the chromosome. These are short runs of 3-4 repetitive base sequences found throughout the genome
2. The chromosomes are then mechanically sheared into their smaller sections of around 100,000 base pairs (called the shotgun approach)
3. The sections of DNA are now inserted into plasmids called BAC (Bacterial, artificial chromosome )

hope this helps

Reply 42

matt7

Hopes for tomorrow... long answer questions on technical aspects of genetic engineering, sequencing, DNA manipulation, action of muscles, etc.

More realistically... page after page of vague 3-mark questions on biodiversity, succession, ecology, etc.

YAY FOR ECOSYSTEMS :rolleyes:

Reply 43

jacko0892

Good Luck to everyone tomorrow...lets hope those pesky seals dont get us again!

Reply 44

TX22

if there is a 8 MARKER ON genetic engineering or DNA stuff, i will PISS my pants with excitement

Good luck 2 evry1.

Hmm, let the post exam dissection commence.

I didn't think it was too bad. I know I threw away a few easy marks on some of the simpler questions, but overall I think I wrote the right kind of stuff, especially for the 8 markers (in fact, I wrote too much for the first). Scary thing is though, this is how I felt in January and it turned out I did really badly.

I need 75% UMS which hopefully will be covered by what I wrote, though with the number of people saying they liked it or didn't think it was too bad, it might have been an easier paper and the UMS boundaries might shoot up.

Reply 47

Magma828

Will there be an unofficial copy of the paper and a mock-up mark scheme soon?

Reply 48

Schismist

TX22

if there is a 8 MARKER ON genetic engineering or DNA stuff, i will PISS my pants with excitement

Did you? Did you? :rolleyes:

You lucky person!

I was pretty happy too, but I waffled about being antibiotic resistant to 2 different things, and got confused how to end up with only the right culture and just decided to bluff so I hope they don't read it too carefully

Reply 49

ibbyibz

I thought the paper was ok, although i did get confused on afew questions, which ment i lost afew marks here and there.

Reply 50

Chaosworld

Yeh the paper was better then the jan f214 paper, the two 8 markers questions were a gift!!!!

Reply 51

lossy1234

on the 8 marker for genetic engineering did u guys write about how its done with insulin and replica plating etc.. ? and for the other one it was transcription translation right ?

Reply 52

Chaosworld

i am not so sure about the replica plating because as far as i remeber the question asked for how renin is made by genetic modification

rennin = ew

it was ok, defo better than jan... but it was a baffling exam :/

Reply 55

bangla_man

harldy anything on muscle contraction, brain parts. nd dopamine the abosukte last paper in the book came a lot
clever pricks.. did ok i gues, chi squared remarbly straight forward expected for both 25. rushed the second 8 marker cause i came back to it, some confusing questions overall not bad.. for firsty 8 mrker bsicaly input relinin instaed of insulin ans described the whole processs....

Reply 56

SHAYAN1369

What colour did u get for drosophila's eye colour guys? The 3 marks question about VvBbCc(I think was red) vvBBCC(White I think) but I'm not sure :frown:

Reply 57

ibbyibz

i wasnt sure about the eye colour aswell, i just hoped for the best and guessed :s-smilie:

Reply 58

Chaosworld

wat did u guys put for the question on which mutation lead to most serius consequences & why for the following:

21 base pair deletion, 13 bas pair deletion or silent mutation

Reply 59

nameless_one

Chaosworld

wat did u guys put for the question on which mutation lead to most serius consequences & why for the following:

21 base pair deletion, 13 bas pair deletion or silent mutation