Answer:
A
Explanation:
Because there are two DNA strands in the DNA molecule and they both rotate around each other in a helix formation. So two helixes = double helix.
Lactase refers to an enzyme that can dissociate lactose sugar into glucose and galactose. This enzyme plays an important role in the digestion of milk that comprises high lactose sugar. In case, if a mutation occurs in the gene codon of lactase, then two possibilities can take place. These are as follows:
1. Loss of mutation: In this case, the person becomes lactose intolerant because of mutation in lactase gene codon. Due to this, there is low mRNA expression and thus low production of the enzyme lactase. This is also known as lactase non-persistent phenotype.
2. Gain in mutation: In this case, the person gain an increase in mRNA expression of the lactase gene, thus more production of lactase takes place than usual. This kind of individual exhibits lactase persistent phenotype.
The answer is A, convergence.
I’m sorry can u translate it to english!
Answer:
p53 helps the cells from passing on mutations that lead to DNA damage. Hence, it is known as the guardian angel of the cell as it helps fight against cancer. However, if p53 becomes defective or missing, then the mutations will lead to cancer.
Mutations in the p53 can also cause the tumor-suppressing genes to convert into tumor causing genes. Hence, mutations in such kind of genes can be very harmful for the body.