PATHOLOGY MCQ
CELL DAMAGE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Death-promoting signals e.g TNF
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Withdrawal of stimulatory signals e.g EGF
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DNA damage
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Extrinsic factors e.g infection and trauma
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Detailed explanation-1: -Following the induction of DNA damage, a prominent route of cell inactivation is apoptosis. During the last ten years, specific DNA lesions that trigger apoptosis have been identified. These include O6-methylguanine, base N-alkylations, bulky DNA adducts, DNA cross-links and DNA double-strand breaks (DSBs).
Detailed explanation-2: -The cell death response to DNA damage is only one of several biological outcomes that can result from cellular exposure to genotoxic stress. These biological responses are temporally regulated such that DNA repair and cell cycle arrest are activated immediately following DNA damage [6].
Detailed explanation-3: -If the DNA can be repaired, p53 activates other genes to fix the damage. If the DNA cannot be repaired, this protein prevents the cell from dividing and signals it to undergo apoptosis. By stopping cells with mutated or damaged DNA from dividing, p53 helps prevent the development of tumors.