1c) Mutation 1 will not affect the amino acid sequence as it will have the same sequence (glycerine) thus the same primary structure as the original due to the combination.

2b) The appearance of the chromosomes is due to the sister chromatids produced as a result of DNA replication. They are held together by the centromere (which can be seen on the diagram in the middle of the chromatids :tongue:

)

2d ii) 8 :smile:

4a)

b)bivalent

c i) Ab, aB

ii) AB, ab

d) independent assortment- it results in a different combination of maternal and paternal chromosomes so more variation.
mutation- this will change the combination of alleles, so again there is more variation.

There you go :tongue:

Reply 6

Desi.Biochemist96

OP

11

Original post by Lucy96

1c) Mutation 1 will not affect the amino acid sequence as it will have the same sequence (glycerine) thus the same primary structure as the original due to the combination.

2b) The appearance of the chromosomes is due to the sister chromatids produced as a result of DNA replication. They are held together by the centromere (which can be seen on the diagram in the middle of the chromatids :tongue:

)

2d ii) 8 :smile:

4a)

b)bivalent

c i) Ab, aB

ii) AB, ab

d) independent assortment- it results in a different combination of maternal and paternal chromosomes so more variation.
mutation- this will change the combination of alleles, so again there is more variation.

There you go :tongue:

Thank u sooo much!!!! for the help!!!
btw can u explain how did u work out 4a, please?

(edited 10 years ago)

Reply 7

Hype en Ecosse

20

Original post by rosie.96

Thank u sooo much!!!! for the help!!!
btw can u explain how did u work out 4a, please?

For 4a, when you've got a big "X" shaped chromosome what that means it's made up of two genetically identical chromatids. So whatever's on one chromatid, must be on the other chromatid, too!
The question says that the person has the genotype "AaBb" - so we know that since they're homologous chromosomes (i.e. both chromosomes contain the same genes) then the other chromosome must have the alleles that the chromosome we labelled first doesn't have. So when one chromosome has an "A", then the other chromosome must have the "a". And it's the same with the B and b's.

If the person had an "AABb" genotype, then that'd tell you that both chromosomes have a big A, but then only one has a big B and the other has a little b. Hope that helps. :smile:

Reply 8

Desi.Biochemist96

OP

11

Original post by Hype en Ecosse

For 4a, when you've got a big "X" shaped chromosome what that means it's made up of two genetically identical chromatids. So whatever's on one chromatid, must be on the other chromatid, too!
The question says that the person has the genotype "AaBb" - so we know that since they're homologous chromosomes (i.e. both chromosomes contain the same genes) then the other chromosome must have the alleles that the chromosome we labelled first doesn't have. So when one chromosome has an "A", then the other chromosome must have the "a". And it's the same with the B and b's.

If the person had an "AABb" genotype, then that'd tell you that both chromosomes have a big A, but then only one has a big B and the other has a little b. Hope that helps. :smile:

Got it thanx :smile:

Reply 9

Desi.Biochemist96

OP

11