I think this is the answer key.. tell if you need help read it :)
It’s c cause I know and I was just too lazy to type the word lol
Reaction which breaks down complex molecules into simpler ones n release energy
Answer:
1. The difference between the normal hemoglobin protein DNA sequence and the sickle cell hemoglobin DNA sequence is a base to base shift, in this case adenine (GAG) to thymine (GTG).
2. The difference affects the amino acid sequence of the protein by replacing glutamic acid (Glu) with valine (Val).
Explanation:
In sickle cell anemia, a change in the DNA nucleotide sequence is observed, where adenine is substituted by thymine, whose expression is the change in the amino acid sequence of globine β, incorporating valine instead of glutamic acid. This represents a molecular mutation - point mutation - by subtitution, which corresponds to missense mutation.
<u>Normal hemoglobin protein in a RBC</u>
DNA CTG ACT CCT GAG GAG AAG TCT
Amino acids Leu Thr Pro Glu Glu Lys Ser
<u>Sickle cell hemoglobin protein in a RBC</u>
DNA CTG ACT CCT <em>GTG</em> GAG AAG TCT
Amino acids Leu Thr Pro <em>Val</em> Glu Lys Ser
When GAG is transcribed to mRNA, the CUC codon is obtained, which codes for glutamic acid. Thymine substitution causes the DNA sequence to change to GTG, which is transcribed as CAC, the codon that encodes the amino acid valine. The <u>change from glutamic acid to valine in β-globin causes an altered hemoglobin, giving the abnormal erythrocytes observed in sickle cell disease</u>.
The proteins exhibit four levels of organization:
1. Primary structure: It refers to a sequence of amino acids join together by the peptide bonds to produce a polypeptide chain.
2. Secondary structure: It is a localized twisting of the polypeptide chain by producing a hydrogen bond. Two types are formed, that is, the alpha helix and beta pleated sheet.
3. Tertiary structure: It refers to the three-dimensional composition of a polypeptide chain. The folding is not regular as it is in secondary composition. It produces ionic bonds, hydrophobic interactions, disulfide bond, and hydrogen bond amongst the polypeptide chains.
4. Quaternary structure: It comprises an amalgamation of two or more polypeptide chains that functions as a single functional unit. The bonds are identical as in tertiary composition.
Thus, the levels of secondary, tertiary, and quaternary protein structure would get affected if all the hydrogen bonding associations were inhibited.
