Answer:
a. p53 activates transcription of WAF1.
Explanation:
<u>WAF1 transcription occurs independent of p53 during oxidative stress so p53 does not play any role in cell cycle arrest in the signaling pathway which involves WAF1 . </u>
In rest of the mentioned options, p53 plays a role directly or indirectly. During double stranded lesion in DNA in G1 phase, a sensor protein known as ATM binds the DNA lesion site. ATM is a serine/threonine kinase which phosphorylates another kinase known as chk2. After phosphorylation,<u> chk2 stabilizes transcription factor p53.</u> p53 further acts as a transcription factor for the synthesis of a protein known as p21 which inhibits G1 phase specific CDK and ultimately cell is arrested in G1 phase. The cell remains in arrested state until the DNA lesion is fully repaired. <u>Hence, p53 indirectly blocks G1 to S transition with the help of p21. </u>
As such <u>WAF1 transcription factor involving pathway</u><u> </u><u>also requires p21 protein for causing cell cycle arrest but in this pathway p21 is not synthesized with the help of p53. </u>
38 chromosomes
<span>The two identical daughter cells resulting from mitosis and cytokinesis are identical in the following ways:1. Mitosis occurs when the nucleus of the cell divides into two identical nuclei, each with the same type and number of chromosomes. The cell's DNA is duplicated during this phase. Sometimes the cell's DNA isn't copied properly resulting in cancer-type cells. 2. Cytokinesis is when the cytoplasm divides into two identical daughter cells. Each cell is genetically identical and both are a similar size. </span>
Answer:
The energy transformation that takes place during cellular respiration is the conversion of glucose (chemical energy) to another form of compound with high energy bonds (adenosine triphosphate) that can be readily used by the body.
