The nitrogenous bases form hydrogen bonds between opposing DNA strands to form the rungs of the "twisted ladder" or double helix of DNA or a biological catalyst that is found in the nucleotides. Adenine is always paired with thymine, and guanine is always paired with cytosine. These are known as base pairs.
Answer:
AGC and ACA
Explanation:
Codons and anticodons are present in the form of triplets.Codons are present on the coding strand of DNA and on mRNA and their anticodon is present on transfer RNA.When codon present on mRNA binds to its anticodon on tRNA then appropriate amino acid is carried by tRNA on ribosomes for protein synthesis. For example, AGC and ACA anticodons are present on tRNA that binds to UGC and UGU on mRNA for amino acid cysteine.
Answer: Option D
Explanation:
The practice which has been prevailing from a long time is considered as culture.Farming is also a type of culture which is being practiced from a longer period of time in the society.
The farming is also a type of culture which was invented somewhere and started spreading from there to other places.
This practice helped mankind in providing food and resources to the people of nation.
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: It retains and transmits important biological information.
Explanation:
