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CELL CYCLE by nurjulaiha roslan. Sequence of stages between cell division and the next. Time taken to complete one cell cycle varies with tissues and among spesis .
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Sequence of stages between cell division and the next. Time taken to complete one cell cycle varies with tissues and among spesis. Enviromental factor such as changes in temperature and pH and declining nutrients levels lead to declining cell division rates. CELL CYCLE
Cells cycle involve 3 continuous stages- -Interphase -Mitosis-Cytokinesis
Phase between mitotic division and appears to be resting phase. • Can be divived to 3 phase • G1 phase • S phase • G2 phase INTERPHASE
RNA and protein produced. Cells grows rapidly. Chromosomes not yet visible. Organelle grows and increase in size. Nucleolus clearly visible. G1 PHASE
DNA replicates. Synthesis of Histone proteins. Chromosomes have 2 chromatids. Chromosomes not visible. S PHASE
Cells increase in mass. More Mitochondria and Chloroplast. Energy store increase. Chromosome start shorten and condense. Replication of Centrioles G2 PHASE
mitosis • Process of dividing a cell by replication and dividing the original chromosomes to obtain 2 new cells identical to one another. • Divided into 4 stages • Prophase • Metaphase • Anaphase • Telophase mitosis
Chromatin in nucleus begins to condense. Nucleolus disappear. Mitotic Spindle begin to form. Centrosomes formed and move apart,push by microtubules. Chromosomes migrate to centre of nucleus. Disappearance of nuclear envelope. PROPHASE
Nuclear envelope breaks up completely. Centrioles have reaches opposite poles. Attaches to Spindle Fibre in the Centromere. Chromosomes line up on metaphase plate. METAPHASE
Centromere divide and 2 chromatids of each chromosomes seperates. Spindle Fibre pull the sister chromatidsappart towards opposite pole of cells. Each poles contain a complete set of chromosomes. ANAPHASE
Spindle fibre disappear and centrioles divide into two. Chromosomes uncoil and return to chromatin form. Nuclear envelope reform. Nuclei begin to form. TELOPHASE
Splitting the cytoplasm that seperates daughters nuclei into two individual daughter cells. • Furrow forms then it will slowly reduces the diameter of cell until it eventually slices all the way into center of the cell. • Cells seperates completely and 2 complete cell form. cytokinesis
For cell replacement For growth To maintain the genetic stability Reproductive development of organism Continual of life or survival of all organisms. Significance of cell division
For more understanding ,watch this video through this link.. YouTube - Mitosis.flvor http://www.youtube.com/watch?v=ATlUv-AGhEU Watch this video!!!