Turn on thread page Beta

OCR 2010 A2 Biology Unit 2 - Control, Genome and Environment watch

Announcements
    Offline

    1
    ReputationRep:
    *posts*
    Offline

    14
    ReputationRep:
    (Original post by osiris6607)
    *posts*
    *Quotes*

    Good Morning people Wakey wakey
    Offline

    12
    ReputationRep:
    Okay, say if in an exam you were asked to 'Outline the stages of meiosis' how the hell would you do there's too much to write. I can't condense my notes to say a 6 mark answer. Helppp :'(
    Offline

    14
    ReputationRep:
    Cloning....animals.....plants... .are you serious, OCR?

    It's official, guys. OCR wants to ruin my entire life.
    Offline

    11
    ReputationRep:
    Just flicked through the biotech module, why OCR? What is with your obsession with route learning? :sigh:
    Offline

    14
    ReputationRep:
    (Original post by I Have No Imagination)
    Okay, say if in an exam you were asked to 'Outline the stages of meiosis' how the hell would you do there's too much to write. I can't condense my notes to say a 6 mark answer. Helppp :'(
    I feel ya anyways here goes just to refresh what i have been learning this weekend:
    Meiosis: Its the formation of 4 haploid cells(each with one chromosome) from a diploid cell (which consists of 2 sets of chromosomes).
    The whole love story goes as following :

    Keys:
    I= Primary, II= Secondary

    I Prophase : Here the chromosomes condense(visible) and form thread like structure.During condensation homologous chromosomes pair up ro form bi-valents.Crossing over of chromatids takes place here which leads to variation, this crossing over is called chiasma.
    Late prophase I:Chromosomes have condensed enough to make them very visible.
    I Meta-phase:
    Nuclear envelope dissappears, centrioles reach to the pole/spindle forms.(hint: it might work for you , think asMetaphase has something to do with "Membrane".
    I Anaphase: Homologous Chromosomes of each bivalent separate and are pulled by microtubules to the poles.<-- This is the step where the number of chromosomes halves.
    I Telo-phase: Chromosomes de-condense,form two nuclei .

    I Cytokinesis: Plasma membrane folds inwards to form 2 cells, centrioles divide to form new spindle.

    HALF WAY THERE: ===============================


    II Prophase :Chromosomes condense.
    II Meta-phase:Nuclear envelope dissappears,chromosomes pulled towards the equator.
    II Ana-phase:Centromere divide each chromatid is a chromosome.
    II Telophase:Chromosomes reach the pole, decondense ,form nuclei.
    Cytokinesis II: Original cell has now produced 4 cells, each half the no. of chromosomes of the parent cell.

    Enter Ibysaiyan.
    Offline

    14
    ReputationRep:
    (Original post by Get Cape.Wear Cape.Fly.)
    Cloning....animals.....plants... .are you serious, OCR?

    It's official, guys. OCR wants to ruin my entire life.
    I know they suck big time, most of the biotech. crap was covered last year..... what a waste.
    Offline

    12
    ReputationRep:
    (Original post by ibysaiyan)
    I feel ya anyways here goes just to refresh what i have been learning this weekend:
    Meiosis: Its the formation of 4 haploid cells(each with one chromosome) from a diploid cell (which consists of 2 sets of chromosomes).
    The whole love story goes as following :

    Keys:
    I= Primary, II= Secondary

    I Prophase : Here the chromosomes condense(visible) and form thread like structure.During condensation homologous chromosomes pair up ro form bi-valents.Crossing over of chromatids takes place here which leads to variation, this crossing over is called chiasma.
    Late prophase I:Chromosomes have condensed enough to make them very visible.
    I Meta-phase:
    Nuclear envelope dissappears, centrioles reach to the pole/spindle forms.(hint: it might work for you , think asMetaphase has something to do with "Membrane".
    I Anaphase: Homologous Chromosomes of each bivalent separate and are pulled by microtubules to the poles.<-- This is the step where the number of chromosomes halves.
    I Telo-phase: Chromosomes de-condense,form two nuclei .

    I Cytokinesis: Plasma membrane folds inwards to form 2 cells, centrioles divide to form new spindle.

    HALF WAY THERE: ===============================


    II Prophase :Chromosomes condense.
    II Meta-phase:Nuclear envelope dissappears,chromosomes pulled towards the equator.
    II Ana-phase:Centromere divide each chromatid is a chromosome.
    II Telophase:Chromosomes reach the pole, decondense ,form nuclei.
    Cytokinesis II: Original cell has now produced 4 cells, each half the no. of chromosomes of the parent cell.

    Enter Ibysaiyan.
    Lol, yay, thanks, +REP for you tomorrow, already used it today.

    This unit is too long.
    Offline

    14
    ReputationRep:
    (Original post by I Have No Imagination)
    Lol, yay, thanks, +REP for you tomorrow, already used it today.

    This unit is too long.
    Sadly it is , lol i hate it.... not that its too complex just over-stretched .....
    Offline

    0
    ReputationRep:
    I just can't get my head around meiosis 2, no matter how much I've tried. Don't know what's wrong with me I just don't get it!
    Offline

    1
    ReputationRep:
    (Original post by Tinkerbelle ♥)
    I just can't get my head around meiosis 2, no matter how much I've tried. Don't know what's wrong with me I just don't get it!
    From what I've learnt, Meiosis II is basically when the cell containing homologous (pair) chromosomes undergoes 'mitotic division' to produce cells with a haploid number (half the number of chromosomes of the parent cell). The stages are very much the same to that in Mitosis but this time in Meiosis II the chromosomes are homologous.
    Offline

    0
    ReputationRep:
    What happens to the 4 daughter cells produced in meiosis? How does this form 1 zygote i.e foetus?

    So confused
    • Thread Starter
    Offline

    0
    ReputationRep:
    (Original post by TheMikester69)
    What happens to the 4 daughter cells produced in meiosis? How does this form 1 zygote i.e foetus?

    So confused
    Im scared lol if this is what is waiting for me after the biotech module:eek3: i like genetics but i probably would struggle a bit, especially on CHI SQUARE lol
    Offline

    0
    ReputationRep:
    (Original post by Remarqable M)
    Im scared lol if this is what is waiting for me after the biotech module:eek3: i like genetics but i probably would struggle a bit, especially on CHI SQUARE lol
    You should be scared.

    (I'm joking :p: )

    It's not that bad really! I can't comment on chi squared. I was away when they covered that so will have to learn it on my lonesome

    The Hardy-Weinburg Principle isn't too much fun either. I suck at maths. Big time.
    Offline

    0
    ReputationRep:
    (Original post by Tinkerbelle ♥)
    You should be scared.

    (I'm joking :p: )

    It's not that bad really! I can't comment on chi squared. I was away when they covered that so will have to learn it on my lonesome

    The Hardy-Weinburg Principle isn't too much fun either. I suck at maths. Big time.
    I agree, but even more big time. Why the hell did they let a mathematician get involved...
    Offline

    0
    ReputationRep:
    (Original post by Remarqable M)
    Im scared lol if this is what is waiting for me after the biotech module:eek3: i like genetics but i probably would struggle a bit, especially on CHI SQUARE lol
    What do you mean?
    Did i ask a really stupid question or something? :/
    Offline

    0
    ReputationRep:
    (Original post by TheMikester69)
    I agree, but even more big time. Why the hell did they let a mathematician get involved...
    I have no idea but I can't do it There's a reason I didn't take maths!!! It's because I suck. Can't get my head around it. Hoping when I get to looking at chi square it's not as bad..
    Offline

    0
    ReputationRep:
    (Original post by Tinkerbelle ♥)
    I have no idea but I can't do it There's a reason I didn't take maths!!! It's because I suck. Can't get my head around it. Hoping when I get to looking at chi square it's not as bad..
    Chi squares :confused:. Not got that far yet, and i'm already so confused.
    Offline

    0
    ReputationRep:
    (Original post by TheMikester69)
    Chi squares :confused:. Not got that far yet, and i'm already so confused.
    No same, I couldn't even tell you what it's for. All I can tell you is it involves maths. And complicated looking symbols. :sigh:
    Offline

    0
    ReputationRep:
    (Original post by Tinkerbelle ♥)
    No same, I couldn't even tell you what it's for. All I can tell you is it involves maths. And complicated looking symbols. :sigh:
    Oh sh...
 
 
 
Reply
Submit reply
Turn on thread page Beta
Updated: May 29, 2014
Poll
Cats or dogs?

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reply
Hide
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.