This discussion is closed.
ahmmm
Badges: 0
Rep:
?
#2501
Report 6 years ago
#2501
(Original post by HovisJeffreys)
Woo, more people from xaverian? ^_^


Posted from TSR Mobile
poos all over loreto!
0
Mocking_bird
Badges: 11
Rep:
?
#2502
Report 6 years ago
#2502
(Original post by ahmmm)
yessssssssssssssssssssssssssssss sssssssss badass :cool: dont think i know of her, ive seen the tall one though! and the kick boxer or thai boxer or something like that :rolleyes:
Yeah its basically the other one thats young, thats not the ones you mentioned ahaha :')

(Original post by ahmmm)
oh and could you explain the part of translation where 'all the codons have been read and a polypeptide is produced' ?? confused... :confused:
Basically like... when all the codons have been read by tRNA and matched to an amino acid
0
guitardad
Badges: 10
Rep:
?
#2503
Report 6 years ago
#2503
(Original post by Mocking_bird)
Transcription:
- Occurs in the nucleus
- DNA stands are split by hydrogen bonds being broken by DNA helicase
- One of the strands acts as a template
- Individual RNA nucleotides align next to the template according to specific base pairing
- The difference being uracil replaces thymine
- RNA nucleotides are joined together by RNA polymerase
- This creates a strand of pre-MRNA which undergoes splicing (removes introns and joins together exons) and leaves through a nuclear pore to the cytoplasm to attach to a ribosome to undergo translation.

Translation:
- Occurs in a ribosomes in the cytoplasm
-Sequence of codons on mRNA is used to determine the sequence of amino acids in a polypeptide and works by:

- Each tRNA molecule has 3 exposed bases called an anti-codon.
- tRNA with the anticodon complimentary to the first mRNA codon will move towards the mRNA strand bringing along the specific amino acid
- Other tRNA join in order determined by mRNA
- Amino acids join together by peptide bonds which require ATP.
- tRNA then begins to move away, leaving behind the amino acids. It collects another amino acid of the same kind so it can be reused.
- This continues until all codons have been read and it reaches a stop codon, and a specific polypeptide is then produced from the sequence of amino acids.
- The polypeptide then folds into secondary/tertiary structures.

FEel free to ask more if something doesnt make sense
these notes are really good! do you have them for the rest of biol5?
0
DavidYorkshireFTW
Badges: 16
Rep:
?
#2504
Report 6 years ago
#2504
Hey guys, if you are completely clueless on the essay tittle, and everything you put is wrong, do you get 0 marks for the essay, or points deducted from the marks you got in the paper?
0
ahmmm
Badges: 0
Rep:
?
#2505
Report 6 years ago
#2505
(Original post by Mocking_bird)
Yeah its basically the other one thats young, thats not the ones you mentioned ahaha :')



Basically like... when all the codons have been read by tRNA and matched to an amino acid
so all the amino acids that join for the polypeptide? :s
i've only had mr simpson and garnzzzz! best teachers around though :cool:
0
Mocking_bird
Badges: 11
Rep:
?
#2506
Report 6 years ago
#2506
(Original post by kingster123)
hey can you please explain the oestrous cycle and the positive an dnegative factors in that please
Sure!
Oestrous cycle:

- Pituitary gland releases FSH into blood -> Stimulates follicles to grow which contain egg
- Follicles secrete oestrogen into the blood and inhibit the release of FSH and LH (negative feedback)
- Follicles continue to grow and produce more oestrogen until day 10 -> reaches critical point which stimulates a sudden surge in LH and FSH (positive feedback)
-Surge in LH causes follicle to release an egg. This is ovulation.
- LH stimulates follicles to develop into corpus luteum which secretes progesterone.
- Progesterone maintains the uterus lining and inhibits FSH/LH
- If the egg isn’t fertilised the corpus luteum degenerates and no longer produces progesterone so lining no longer maintains and breaks down causing bleeding.
- FSH is now no longer inhibited by the progesterone so the cycle can start again.
(This is if fertilisation does not occur).

If fertilisation occurs:

- Embryo will implant in the endometrium which must not break down
- Human chorionic gonadotrophin (HCG) is released to prevent the corpus luteum breaking down
- Placenta gradually takes over the corpus luteum when it begins to secrete most of the progesterone/oestrogen essential for a normal pregnancy.
(HCG is detected in the urine and this forms the basis of a pregnancy test).
0
Ghost95
Badges: 0
Rep:
?
#2507
Report 6 years ago
#2507
(Original post by DavidYorkshireFTW)
I know, which is annoying as I do geography Are you prepared for it?
Not fully, I'll spend a lot of tomorrow doing essay prep I think, but I'm feeling ok about the main exam, been getting decent A's so far but the essay could mess it all up :/


Posted from TSR Mobile
0
Mocking_bird
Badges: 11
Rep:
?
#2508
Report 6 years ago
#2508
(Original post by ahmmm)
so all the amino acids that join for the polypeptide? :s
i've only had mr simpson and garnzzzz! best teachers around though :cool:
I had miss chadwick last year (the tall one) and she was really good!

But yeah So when it gets to the end of the mRNA strand, all of the codons have been read, so therefore all the amino acids will have been brought over by tRNA and joined together to create a polypeptide
0
KaranbirBandesha
Badges: 0
Rep:
?
#2509
Report 6 years ago
#2509
Okay i'm really screwed, i've only just started revising for this exam because i've been revising for my others and i don't even have one of those AQA text books, does anyone have any revision resources that could help me out or any notes that are good as the ones in the AQA text book? please i really need something!!!
1
DavidYorkshireFTW
Badges: 16
Rep:
?
#2510
Report 6 years ago
#2510
(Original post by Ghost95)
Not fully, I'll spend a lot of tomorrow doing essay prep I think, but I'm feeling ok about the main exam, been getting decent A's so far but the essay could mess it all up :/


Posted from TSR Mobile
Same :/ I still need to go over the synoptic stuff I did my first essay on cause of disease the other day and got 18/25 which is alright i suppose, but I am not hugely confident on things like negative feedback :/ That's really good! but yes, this is AQA we are talking about :L
0
ahmmm
Badges: 0
Rep:
?
#2511
Report 6 years ago
#2511
(Original post by Mocking_bird)
I had miss chadwick last year (the tall one) and she was really good!

But yeah So when it gets to the end of the mRNA strand, all of the codons have been read, so therefore all the amino acids will have been brought over by tRNA and joined together to create a polypeptide
the tall one thank you i get all confused with a gene codes for this and dna codes for this and this forms a polypeptide and this forms a gene and the bases codefor this and this codes for that :| is there a simple way of remembering that?
0
Mocking_bird
Badges: 11
Rep:
?
#2512
Report 6 years ago
#2512
(Original post by ahmmm)
the tall one thank you i get all confused with a gene codes for this and dna codes for this and this forms a polypeptide and this forms a gene and the bases codefor this and this codes for that :| is there a simple way of remembering that?
I just memorised it Not really sure of a simple way sorry!
0
Ghost95
Badges: 0
Rep:
?
#2513
Report 6 years ago
#2513
(Original post by DavidYorkshireFTW)
Same :/ I still need to go over the synoptic stuff I did my first essay on cause of disease the other day and got 18/25 which is alright i suppose, but I am not hugely confident on things like negative feedback :/ That's really good! but yes, this is AQA we are talking about :L
Haha too right...I'll also look at some of the mark schemes for essays and see what they're looking for


Posted from TSR Mobile
0
flyylikejetz
Badges: 0
Rep:
?
#2514
Report 6 years ago
#2514
Do we need to know about ADH ? or is it a good additive in an essay ?
0
DavidYorkshireFTW
Badges: 16
Rep:
?
#2515
Report 6 years ago
#2515
(Original post by Ghost95)
Haha too right...I'll also look at some of the mark schemes for essays and see what they're looking for


Posted from TSR Mobile
Yes, that's what I plan to do
0
A learner
Badges: 0
Rep:
?
#2516
Report 6 years ago
#2516
how do yous revise for unit 5? the only way I revise is by going over notes and past papers but we've only got three papers to do and I keep on messing up these ones because the questions dont make any sense to me! If I get a revision guide or maybe practice papers from the old spec, would it help???
0
iPthreefifthteen
Badges: 8
Rep:
?
#2517
Report 6 years ago
#2517
Hey, can someone help me find some likely essays to come up, and any examples of full/close to full mark examples, I'm quite worried about the essay :/
1
MLogan
Badges: 0
Rep:
?
#2518
Report 6 years ago
#2518
What factors influence blood glucose concentration? Is this asking for factors such as diet and exercise?
0
JoshL123
Badges: 2
Rep:
?
#2519
Report 6 years ago
#2519
Does anyone have any ideas for the transfer of energy from unit 1? Maybe active transport but any others?
0
gingerandice
Badges: 1
Rep:
?
#2520
Report 6 years ago
#2520
hey yall? can I post a shapes fitting eassy from june 2012? I just want to know if im actually answering the question and possible feedback? x Shapes fitting together.

I post it below?
0
X
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

University open days

  • University of Bristol
    Undergraduate Open Afternoon Undergraduate
    Wed, 23 Oct '19
  • University of Exeter
    Undergraduate Open Day - Penryn Campus Undergraduate
    Wed, 23 Oct '19
  • University of Nottingham
    Mini Open Day Undergraduate
    Wed, 23 Oct '19

Have you made up your mind on your five uni choices?

Yes I know where I'm applying (144)
60.25%
No I haven't decided yet (54)
22.59%
Yes but I might change my mind (41)
17.15%

Watched Threads

View All