Question

In a mutational event, when adenine is replaced by guanine, it is a case of:
A. Frameshift mutation
B. Transcription
C. Transition
D. Transversion

Answer 1

Hint: Changes to an organism's DNA sequence are referred to as mutations. Viral infection, exposure to mutagens, or errors in DNA replication during cell division can all result in mutations.

Complete step by step solution:
The two types of mutations known as frame-shifts are insertions and deletions, which are the type of mutations. When nucleotides that are not multiples of three are added or removed, the reading frame of the genetic code will change. Insertions change the DNA by introducing one or more additional nucleotides. Our DNA base pair sequence can alter due to environmental variables like UV light or errors made during DNA replication, which are both examples of environmental influences.
Because it generates a new DNA sequence for a particular gene, mutation is crucial as the initial stage of evolution because it results in the creation of a new allele. Recombination can also result in a new DNA sequence (a new allele) for a specific gene through intragenic recombination. While the majority of mutations are advantageous, some can be harmful.
A risky mutation could result in a genetic disorder or a malignant condition. Another sort of mutation is a chromosomal one. Chromosomes, which are little, threadlike organelles present in the cell nucleus, carry genes. A DNA nucleotide mutation can cause one or more genes to mutate. a variety of genes changing. one or more genes are lost. Both somatic and germ-line cells are susceptible to mutation. When an organism reproduces sexually, germ-line mutations take place in the reproductive cells (sperm or eggs) and are passed on to the offspring.
A transition is a point mutation that transforms one nucleotide from one type of purine to another (A -> G) or from one type of pyrimidine to another (C —>T). Transitions make up about two out of every three single nucleotide polymorphisms. Oxidative deamination and tautomerization can lead to transitions.
So, option (C) is correct.

Note:
Additional human mutation examples include Angelman syndrome, Canavan disease, color blindness, cri-du-chat syndrome, cystic fibrosis, Down syndrome, Duchenne muscular dystrophy, hemochromatosis, hemophilia, and Klinefelter syndrome.