#Question id: 19923
#Unit 12. Applied Biology
#Question id: 20279
#Unit 7. System Physiology – Animal
#Question id: 1513
#Unit 4. Cell Communication and Cell Signaling
The kinase activity of ATM is activated in response to DNA damage due to various stresses (e.g., UV irradiation, heat). Activated ATM then triggers following pathways leading to arrest in G1.
A. Chk2 is phosphorylated and, in turn, phosphorylates Cdc25A, thereby marking it for degradation and blocking its role in CDK2 activation.
B. Phosphorylation of p53 stabilizes it, permitting p53-activated expression of genes encoding proteins that cause arrest in G1, promote apoptosis, or participate in DNA repair.
C. Controlling the pool of p53, ATM phosphorylates MDM2 to inactivate it, causing increased stabilization of p53. Another protein p14ARF inhibits the activity of Mdm2 thus stabilizing p53.
Based on the above information, which one of the following statements is correct?
#Question id: 10224
#Unit 6. System Physiology – Plant
Exposure to high levels of excess light that damage the photosynthetic system and decrease both quantum efficiency and maximum photosynthetic rate results
#Question id: 32927
#Unit 2. Cellular Organization
