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A level Biology: Post your doubts here!

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I face trouble solving paper 3 in biology my exam is on Wednesday and I dont know how to prepare for it what should I do??
and can anyone show me how to draw plan diagram in question 2 may/june variant 33
 
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I face trouble solving paper 3 in biology my exam is on Wednesday and I dont know how to prepare for it what should I do??
and can anyone show me how to draw plan diagram in question 2 may/june variant 33
Do you have excess to biology book of new edition.....you can find the ways for drawing plan diagram on the book......
 
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Heeey guyss how was ur Paper's 1/1 and 5/1

WE're allowed to discuss now ....Come on lets check our answers together !
 
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GUYS what was the answer for these questions in BIOLOGY/9700/paper 11
1- Which process is the least affected by a change in the fluidity of the membrane ?
2-What is the MINIMUM number of membranes that are crossed by oxygen and carbon dioxide molecules ?
3-some thing about the hemoglobin protein structure ( I think that which of the protein structures of the hemoglobin are codded by DNA or some ting like this )
 
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GUYS what was the answer for these questions in BIOLOGY/9700/paper 11
1- Which process is the least affected by a change in the fluidity of the membrane ?
2-What is the MINIMUM number of membranes that are crossed by oxygen and carbon dioxide molecules ?
3-some thing about the hemoglobin protein structure ( I think that which of the protein structures of the hemoglobin are codded by DNA or some ting like this )


well No. 1 I'm doubting .. I guess I did wrong
No. 2 ...I marked in which there were 5 membranes for oxygen ..
bcuz
1. Into the cell of the alveolus
2. Out of the alveolus
3. Into cell of the capillary wall
4. Out of the cell of the capillary wall and into blood plasma
5. Into the red blood cell.
And No. 3 I don't xactly remember the question :/
 
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Can someone please explain how polyploids are formed through hybridisation??

Polyploids is when the chromosome number of an organism increase to more than 2n, if the it is an odd no. eg 3n, 5n they are infertile as they cannot undergo meiosis as homologous paring of chromosomes cannot take place. If it is even then homologous paring can take place and therefore they are fertile
Hybridization is when two gametes of different species are allowed to fuse together to form an offspring eg, is a mule it is formed from a horse and a donkey. Hybridized organism are usually show more better characteristics of both the parents the mule shows both the characteristics of the horse and donkey

Hybridized individuals are always infertile as they cannot undergo meiosis, but sometimes during the formation of gametes they skip meiosis and the gametes have 2 sets of chromosomes ie, 2n. if two individuals who undergo this faulty division mate the resulting offspring is polyploids

If you have the biology application booklet it is explained the genetic engineering section
 
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This
[PA] explain how the anatomy and physiology of the leaves of C4 plants such as maize or
sorghum are adapted for high rates of carbon fixation at high temperatures in terms of:
• the high optimum temperatures of the enzymes involved
• the spatial separation of initial carbon fixation from the light-dependent stage
(biochemical details of the C4 pathway are not required);
And
outline the following examples of crop improvement by genetic modification and include any
associated detrimental effects on the environment or economy:
• herbicide-resistant oil seed rape
• insect-resistant maize and cotton
Explain this plz : S
 
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