Mitosis Flashcards
What is Mitosis?
The formation of 2 new genetically identical daughter cells.
What is Mitosis used for?
It is how organisms grow and is the basis for simple asexual reproduction.
How many chromosomes in human body cells?
23 pairs, 46 in total.
What happens during Interphase with DNA?
DNA combines with proteins called histones to form a dense complex called chromatin.
What happens in Early Prophase?
-The chromosomes become more distinct.
-The centriole divides.
-The nucleolus becomes less prominent.
How do the chromosomes become more distinct?
-They coil up
-Get shorter and thicker
-take up stain more easily
What happens in Late Prophase?
-Chromosomes are more distinct and appear as 2 chromatids.
-Centrioles migrate to opposite poles of the cell.
-Nucleolus shrinks and disappears
-Nuclear enveloped disintegrates.
What happens in Metaphase?
-Each centriole is at a pole. They produce spindle fibres.
-Spindle fibres attach to the centromere of the chromosomes.
-Each centromere is attached to both poles.
-Chromosomes are pulled to the metaphase plate.
What happens in the Anaphase?
-Spindle fibres contract
-Centromere divides
-Each chromatid is pulled to opposite ends.
-Each half of the cell receives one chromatid from each chromosome.
What happens in Telophase?
-Chromatids reach the poles.
-They begin to uncoil and becomes less distinct.
-The nuclear envelope starts to reform.
-NOW KNOWN AS CHROMOSOMES
What happens in Cytokinesis in Animal Cells?
-Cell Divides
-Starts by constriction from edges of the cell.
-Cytoplasm and Cell membrane are pulled inwards into the cleavage furrow.
What happens in Cytokinesis in Plant Cells?
-A cell wall is laid down.
-Vesicles containing cellulose line up down the middle of the cell.
-Cellulose is released, forming the cell wall separates the cell membrane and cytoplasm.
