D) Methanogen is the awnser
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>.
Involuntary as the muscle is a reflex
Answer: (1) Providing an optimized orientation of the substrate.
(2) Decreasing the ∆G in reaction.
(3) Excluding excess water.
Explanation: The active sites of enzymes increase the rate of reaction because they decrease the activation energy of the reaction,and the physical microenvironment provides an optimal orientation of the substrate relative to reactive functional groups while excluding excess solvent,such as water.
Although some active sites may have amino acids that form salt bridges with the amino acids from a substrate,not all do, so this is not a generic strategy of active site microenvironments
*Gotten directly from Quizlet*
