7.3.1 Sickle Cell anaemia
· On chromosome 11, the 17th nucleotide of the gene that codes for the beta chain of haemoglobin is changed from an 'A' to a 'T'. (GAG to GTG) à WRONG!!!
· This changes the mRNA codon from 'CUC' to 'CAC' à WRONG!!!, resulting in the 6th amino acid of the chain being changed from glutamic acid to valine. The R side chain of glutamic acid is a polar whereas that of valine is hydrophobic. The mutant haemoglobin is known as Haemoglobin S (HbS).
· This substitution of one single base in the beta globin gene alters the quaternary structure of haemoglobin, which has a profound influence on the physiology and wellbeing of the individual.
To change the above to:
7.3.1 Sickle Cell anaemia
· On chromosome 11, the 17th nucleotide of the gene that codes for the beta chain of haemoglobin is changed from an 'T' to a 'A'. (template 3’ CTT 5’ to 3’ CAT 5’) à CORRECT
· This changes the mRNA codon from 5' GAA 3' to 5’ GUA 3' à CORRECT, resulting in the 6th amino acid of the chain being changed from glutamic acid to valine. The R side chain of glutamic acid is a polar whereas that of valine is hydrophobic. The mutant haemoglobin is known as Haemoglobin S (HbS).
Hello Miss Teong!
ReplyDeleteMay I know what's the difference between Okazaki Fragments and Lagging Strand? Or are they the same?
Thanks! ;D
Hi,
DeleteIt is not really the same thing. In a way, there are many okzaki fragments but only 1 lagging strand (that is synthesized discontinuously).
All the okazaki fragments in totality will make up the one lagging strand.
Ms Teong
Hi ! =D
ReplyDeleteWhy is there no need for a primer during transcription?
Thank you!
Only DNA Polymerase requires a primer!!
DeleteMiss Teong
On pg 22 of lecture notes for DNA and Genomics,Fig6.1.3 shows a DNA of a prokaryote or a mRNA?
DeleteIs there a difference between mRNA and mRNA transcript?
Delete1) pg 22 shows a mRNA, as stated in the title clearly. why do u thk it is DNA?
Delete2) nope, mRNA is called a mRNA transcript becos it is formed after transcription.
Ms Teong