Hello ?,
Can I have some help on these biology questions, I have tried them but I’m really stuck on how they should be answered, and what the correct answer is.
I have attached the whole questions, but the ones I need help on are 2.2( the fibre one), 2.3,4.1,8.4 and all of 10.
Forget to add the pics.
@mahnoor I have attached the images now, I didn’t realise that they were missing earlier.
Also, thank you so much for helping me on these questions, really appreciate it!?
..
2.1
substitution of a base results in a different triplet in the gene.
this different triplet will code for a different amino acid
as the sequence of amino acids is now different, the primary structure of the polypeptide is also different
8.4
The DNA fragments are moving towards the positive end (from top to bottom) so the heaviest ones would move the slowest (and thus cover the least distance). The ones at the top would thus have the greatest number of bases and the size decreases as you move downwards. You can then compare all the other lanes to lane 1. The ones that match/line up are the same size/ same number of bases.
2.2
Bone marrow cells are undifferentiated (pluripotent stem cells) so they can specialise into red blood cells (which will not be sickle shaped). The patient's own faulty bone marrow cells are destroyed so no more faulty red blood cells are produced. Since the donor is the patient's relative, it also reduces the chances of immune response against the transplanted bone marrow cells.
10.3
The single-stranded DNA molecules have a complementary base sequence to the gene coding for huntingtin protein. It essentially acts as an inhibitor so it prevents RNA polymerase from binding to the gene and thus no mRNA will be formed. No transcription and hence no translation so no protein can be formed.
