B2.1.4 Flashcards
Why does mitosis occur
Where body cells divide to replace worn out cells to repair damaged tissue and to allow for growth.
What is mitosis
mitosis is the process by which each cell divides to form two genetically identical daughter cells
How is DNA replicated
Cell copies its chromosomes so the new cells produced will have a complete set of genetic material.
What is DNA replication
DNA unzips forming two separate strands
DNA bases on each strand are exposed
Free nucleotides in the nucleus line up against each of the strands forming complementary base pairs
This forms DNA base pairs
Whole strand complete there are two identical molecules of DNA
Movement of chromosomes
Chromosomes line up across the centre of the cell.
identical copies of each chromosome, formed when DNA replicated, separate and move to opposite ends of the cell.
Each end now contains a full set of identical chromosomes.
Two new nuclei then forms
What is the last stage mitosis
The cell then pinches inwards to separate the two new nuclei and splits the cell into two genetically identical daughter cells.
What are the stages of the cell cycle
Cell growth -> synthesis (DNA replication) -> cell growth -> mitosis -> cytokinesis.