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.
Answer: e. All of the above
Explanation:
The processing of mRNA to a fully mature eukaryotic mRNA requires addition of a 5' cap (Capping) and 3' poly(A) tail ( polyadenylation) to the ends of the transcript, and removal of any intervening introns by splicing. Once processing is completed, the mRNP, which consists of mRNA and associated proteins, is ready for export from the nucleus.
During the initial exposure to the allergen, contact is made with B cells, these B cells differentiate and produce IgE antibody. The IgE antibodies which works against the allergens are released into the blood stream where they binds to Fc receptors which are located on mast cells and basophils. Now, the mast cells has become sensitized and they will wait patiently for the second exposure. When contact with the allergen is made the second time, the allergen becomes attached to the IgE present on the mast cells and this result in degranulation which trigger a lot of allergic responses.
Answer:
Hox genes are thus a subset of the homeobox transcription factor genes. In many animals, the organization of the Hox genes in the chromosome is the same as the order of their expression along the anterior-posterior axis of the developing animal, and are thus said to display colinearity.
Explanation:
Hox genes, a subset of homeobox genes, are a group of related genes that specify regions of the body plan of an embryo along the head-tail axis of animals. Hox proteins encode and specify the characteristics of 'position', ensuring that the correct structures form in the correct places of the body.
Chromosomes are thread-like structures present in the nucleus, which carries genetic information from one generation to another. They play a vital role in cell division, heredity, variation, mutation, repair and regeneration.
