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>.
Answer:
The correct answer will be- phloem transports photsynthetic products to the roots
Explanation:
Phloem is the vascular tissue which specializes in transporting the solute molecules like sugar in the form of sucrose to in the plants.
The phloem connects the photosynthetic organ (Leaves) to non-photosynthetic organs (stem and roots) of the plants by transporting the photosynthates or sucrose to various parts.
Since the roots also need the energy to perform metabolic functions so need the photosynthates to synthesize the energy molecule. They receive the photosynthates from the phloem.
Thus, phloem transports photosynthetic products to the roots is the correct answer.
Hydrogen bonds exhibit the stronger intermolecular force, and water is a polar molecule, so the hydrogen bonding create strong forces which take more energy to break (causing the surface tension of water), and due to the polarity water molecules “stick” to one another which causes the edges to rise up in a tube, forming a meniscus