Edexcel IAL Biology Unit 5 (WBI05) Scientific Article Discussion - June 2016

Maynn this was so helpful.. Thanks ^______________^

Can someone please tell me that when you're doing pcr experiment, do you add primers and nucleotides at the begining of after step 1 in which DNA strands seperate???

To write an experiment, you must use CORMS.
C - control: always include a control in your experiment, eg for the light intensity leaf experiment have an empty test tube with just some indicator in it...
O - organism: what organisms will be involved and what similarities do they need to have eg. same sex, age, health, ect
R - repetition: how many repeats do you do to make it more practical?
M - measurement: what do you plan to measure? eg growth length temperature weight size ect.
S - standard: what do you need to keep the same? eg time, diet, oxygen, light intensities pH ect

There is no other pattern because all experiments are different. But in order to plan an experiment? Bottom line, Use CORMS.

I try starting it with mentioning dependent and independent variable.
Then I write what needs to be kept same,
followed by how do we measure dependent variable
and then the conditions e.g temp or light or watever we know,
write a control group for your experiment
and end with stating repeats!

I love you guys

Are you guys prepared for biology unit 6 on 13th ?

Summary notes for unit 6 bc I haven't found the thread for it

when describing an experiment:
-state dependent and independent variable and state how to measure the independent (dcpip, counting, measuring length, etc)
-5 diff. values for dependent variable (e.g. temperature - 5, 10, 15, 20, 25 deg) and how to control (waterbath/incubator,etc)
-refer to REPEATS.
-try come up with a control
-state a variable to keep constant for validity (usually source of organism or pre-treatment, or fruit from same source)

writing null hypothesis:
-''no significant correlation between (dependent) and (independent) variable
OR
-''no significant difference between (dependent) and (independent) variable
-use correlation when comparing a range of values, use difference when comparing 2 diff values.

detailed method of experiment (same as describing PLUS these):
-mention time period (example: leave for 48 hours)
-2 variables to control and how to keep them constant (this gives 4 marks so MAKE SURE YOU DO IT)
-description eg. aseptic conditions

when it asks to record, present and analyse data:
-calculate the rate/growth/change
-calculate means
-draw table w/ headings and units
-sketch graph w/ headings and units
-say ''use spearmans rank to determine correlation''

I have a question tho if anyone knows the answer.
On some questions it says ''the student applied a t-test to explore significance blah blah blah, she obtained this result, the table below shows critical values for t-test calculations'' how the hell do u draw conclusions from that

I know it's quite long but can anyone explain gel electrophoresis? the whole thing.
Idk what it is, what it does, how to do it, anything

I hope it's no bother but could anyone tell me how a mast ring is used? Has it got discs at the end of each of its arms onto which the antibiotic is added?
Thank you

A mast ring is a ring which has antibiotic impregnated discs at its tips. Using forceps, you place the mast ring onto the petri plate with the bacterial culture and incubate it. Clear zones will form around the various discs provided that the bacterium is not resistant to that particular antibiotic. Hope that makes sense :P

Yes, thank you
But how do I add the antibiotics to it? Have you got a clue?

It comes with the antibiotics at its tips so you don't have to add the antibiotics to it

Oh, alright. Thank you loads

I love you guys

I hope it's no bother but could anyone tell me how a mast ring is used? Has it got discs at the end of each of its arms onto which the antibiotic is added?
Thank you

our teacher wanted us to make some questions and although these are made just for the sake of it, i hope they help at least a little

thankyou for sharing! X