True about Apoptosis are all except :
**Core Concept**
Apoptosis is a form of programmed cell death, a vital physiological process that eliminates damaged or unwanted cells, maintaining tissue homeostasis and preventing disease. It is characterized by a series of morphological and biochemical changes, including cell shrinkage, DNA fragmentation, and membrane blebbing.
**Why the Correct Answer is Right**
Apoptosis is a highly regulated process involving the activation of caspases, a family of cysteine-aspartic acid proteases. Caspases cleave various cellular substrates, leading to the characteristic morphological changes of apoptosis. Key players in the apoptotic pathway include Bcl-2 family proteins, which regulate the mitochondrial pathway, and the extrinsic pathway, mediated by death receptors on the surface of cells. The intrinsic pathway involves the release of cytochrome c from mitochondria, activating the caspase cascade.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because apoptosis can be triggered by various stimuli, including DNA damage, oxidative stress, and withdrawal of growth factors.
**Option B:** This option is incorrect because apoptosis is a highly regulated process, and dysregulation of the apoptotic pathway is associated with various diseases, including cancer and neurodegenerative disorders.
**Option C:** This option is incorrect because apoptosis is a vital process that maintains tissue homeostasis and prevents disease, rather than causing disease.
**Clinical Pearl / High-Yield Fact**
A key feature of apoptosis is the absence of inflammation, as the dying cells are quickly phagocytosed by professional phagocytes, preventing the release of pro-inflammatory mediators.
**Correct Answer: A. This option is incorrect because apoptosis can be triggered by various stimuli, including DNA damage, oxidative stress, and withdrawal of growth factors.**