Plant Science Resource

  Strict cell cycle regulation is vital to ensure faithful segregation of genetic material and survival of organisms. Proper regulation of cell cycle allows normal development and maintenance of   multicellular organisms including plants and animals.Failure to coordinate such regulation processes leads to genome instability, often associated with birth defects and cancer. Such regulations are of two types namely control point regulation and check point regulation.     Cell cycle checkpoints: Cell cycle checkpoints are control mechanisms that ensure the fidelity of cell division in eukaryotic cells. These checkpoints verify whether the processes at each phase of the cell cycle have been accurately completed before progression into the next phase. Checkpoints occur throughout the cell cycle. It control the orderly progress of cell through the cell cycle, which prevent one stage from proceeding unless necessary earlier stages have been completed.Checkpoints assess the readines of th

  APOPTOSIS The term “apoptosis”   appears in biological literature in1972, to describe a structurally distinctive mode of cell death leading to the cell loss within living tissues. Now a days, it is   considered as a cellular the suicidal mechanism that occurs during development of plants, bacteria, invertebrates and mammals including humans. .In Multicellular organisms, apoptosis is very important, because in these organisms homeostasis is maintained through a balance between cell multiplication and apoptosis.                                   Apoptosis may be defined as the programmed cell death in which   the cell actively participates in bringing about it’s death. During programmed cell death some changes occur in the apoptotic cell, which are as follows……………. (i) First a pronounced increase in cell volume takes place. (ii) Then the modification of the cytoskeleton occurs (iii) The cell membrane starts to form blebs, or regions that balloon out (iv) The nucleus shrink