Edexcel biology unit 6 6bio8 SOS Watch

hey all

am currently sitting this paper, am a private candidate and kinda lost i dnt have any resources to study from, i tried getting the technical book but i couldn't Sad
so please can anyone share with me his/her notes or tell how to prepare for the 8 core practicals

thanks in advance

Hi, I'm currently at uni doing neuroscience, so did A level Biology last year. While I don't know your spec unit, if you tell me the titles of the practicals I can type up some key things about each for you x

5.1 Study on the ecology of a habitat
5.2 Effects of temperature on the development of an organism
6.1 DNA amplification using PCR
6.2 Gel electrophoresis
6.3 Effect of different antibiotics on bacteria
7.1 Investigating respiration
7.2 Effects of exercise on tidal volume and breathing rate
8.1 Investigating habituation to a stimulus

follow this link, i just posted the student notes that you can study these experiments from:
http://www.thestudentroom.co.uk/show...1229919&page=2

Right, I don't know how much exactly you know, but here's some key things:

5.1. Quadrate frames - laid on the groud, record the number of different species as well as the number of each individual animal. Generally impractical to do a whole area, so random (reduced bias) samples are taken and an average per square m is calculated. Consider the size of a quadrat (usually 1m squared).
To sample animals you obv need to catch them :P: nets for insects/aquatic creatures, pitfall traps for walking insects, pooters (one of the sucky things) to catch individual insects, and tulgren funnels extracts small animals from soil samples
It's also worth wiki searching the mark-release recapture method (I can't write the formula down here, but it's worth looking for )

5.2. effects of temperature I imagine will mostly be wanting to know about enzymes and their optimal temperature, so divise an experiment with a control (room temp) and several gradations of temperature, use some sort of rat or mouse or insect if needs to be animal based, or plant if not. Plant might be a good one to write about as then you also need to put about limiting factors.

6.1. The PCR gets millions of copies of DNA! This is useful if you have a particularly small sample (i.e. blood when used for forensics). DNA heated to 95C to break H bonds (but not the ribose-phosphate backbone), so broken into separate strands but doesn't fall apart. Primers (short pieces of DNA) are attached to the DNA to tell the enzyme where to start copying. They also stop the 2 DNA strands from re-joining.
DNA and primer mixture is cooled to 40C so primers fully bind to DNA.
Free nucleotides and DNA polymerase are added and the whole mixture is heated to 70C. Original strands are used as a template.
Cycle starts again...each cycle doubles the amount of DNA so 1, 2, 4, 8...etc

6.2. Use spec. Restriction endonucleases to cut up the DNA into fragments. The pattern of fragments is different for everyone.
DNA fragments are put into wells in a slab of gel. Gel is covered in a buffer solutions that conducts electricity.
An electrical current is passed through the gel. DNA frags are negatively charged so move toward the pos. electrode. Small fragments travle faster so move further toward the positive electrode through the gel.
To see the pattern use gene probes. (I suggest wiki again )

Right...hope this helps for now, I have to go now, but I'll be back later, promise let me know if there are any qus so far
When the current is switched off all the fragments are welll separated.

ahhhhhh thaaanks blaad!!! ama do some studying and get to u later to

The other guys post probs makes mine redundant! :P lol but hope i help any way. Here's a respiratory prac I did earlier this year, it might help though ignore if it doesn't! I won't be offended!
You can message me spec questions if you get stuck on any revision, who knows? It might help my own revision! :P:

ooooh thaanks thats such a good report, but its too advanced for me its really good ur style will inspire me for medical uni next year.

i just got a question what does a "t-test to the data to test his hypothesis" mean??

duuude thanks alot those notes saved me, but do u have the teacher/lecturer sheets??? am studying this alone and got no teacher to tell me the notes ... it will be great if u can upload them thanks in advace