Molecular Biology Tutorials

Difference between Necrosis and Apoptosis: A Comparison Table


necrosis vs apoptosis

Apoptosis vs Necrosis
(Similarities and Differences)

Apoptosis and Necrosis are two types of cell death occur in organisms. The cells undergo death when the cell death becomes necessary as a part of developmental process or they fail to adapt to injuries. Both these types of cell deaths differ in their initial cause and progression of the cell death pathway.

Apoptosis definition (programmed cell death): a physiological process by which unwanted or useless cells are eliminated during the development and other normal biological processes. Often found during tissue homeostasis, embryogenesis, immunological reactions and development of nervous systems. During apoptotic cell death, the cells undergo some characteristic events such as chromatin condensation, nuclear and cytoplasmic aggregation and partitions of cytoplasm and nucleus into membrane bound vesicles called apoptotic bodies containing ribosomes and mitochondria. Apoptotic bodies are recognized and phagocytized by either by macrophages or adjacent cells and thus no inflammatory response are elicited during apoptotic cell death.

Necrosis definition: (accidental cell death) a pathological process occurs when the cells are exposed to serious physical or chemical insults. Occur during pathological infections such as bacterial and fungal infections, hypothermia and hypoxia conditions. The cell and cellular organelles swell and ruptures to release the entire cell content including lysosomal enzymes into the extracellular fluid.  Due to this, necrotic cell deaths are always associated with severe inflammatory response in the surrounding tissues.

The current post describes the similarities and difference between apoptotic and necrotic cell death with a comparison table.

Similarities between Apoptosis and Necrosis

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Molecular Biology Tutorials

Cell Cycle Checkpoints in Regulation of Cell Division and Cancer


Cell Cycle Checkpoints and Cancer

Cell Cycle Checkpoints and Regulation of Cell Cycle

What is cell cycle checkpoint?

Every cell in our body pass through a series of different stages in a cyclic manner called cell cycle.  Cell cycle is a sequential step that taking place in a cell leading to the accurate duplication of genetic materials (DNA), precise separation of replicated genetic materials and passing them in to two daughter cells.  The process of cell cycle is very critical in each cell, thus it operate strictly under strong surveillance to prevent any mistakes. This strong surveillance system in the cell to monitor the cell cycle progression itself is called cell cycle checkpoints. Checkpoints are surveillance mechanisms that halt the progress of cell cycle if (1) any of the chromosomal DNA is damaged, or (2) critical cellular processes, such as DNA replication during S phase or chromosome alignment during M phase, have not been properly completed. Thus cell cycle checkpoints ensure that the various events in the cell cycle progression occur accurately and in correct order. In this post we will discuss the three types of cell cycle checkpoints that operate in eukaryotic cells during cell cycle progression.

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