Cell Division, Differentiation Flashcards
What are the 2 main stages of the cell cycle
Interphase
Mitosis
What are the 3 cell cycle checkpoints
G1
S
G2
Why are there cell cycle checkpoints
Prevent uncontrolled division (Cancer)
Detect damage to DNA and cells
What is the name of the process where a faulty cell is detected and destroyed
Apoptosis
Where are the 2 main checkpoints found
between: G1/S and G2/M
What happens in the S phase of the Cell cycle
DNA synthesis
What is the function of cell division
Growth: organisms grow by producing more cells that are genetically identical to each other
Repair: Wound and tissue damage are healed by tissues producing more cells to replace damaged ones
What is meant by Asexual Reproduction
Where single celled organisms (like amoeba) divide by mitosis to form new individuals
What are the 4 stages of Mitosis
Prophase
Metaphase
Anaphase
Telophase
What happens during prophase
Chromosomes condense (become visible under microscope)
Breakdown of nuclear envelope
Centriole divides and daughter centrioles move to poles of cell
Spindle fibres start to form (make of tubulin from cytoskeleton)
What happens during metaphase
Chromatid pairs line up down the equator
Join onto the spindle fibres by their centromeres
What happens during anaphase
The centromere splits
Motor proteins pull the chromatids in opposite directions towards the poles
What happens during telophase
The chromosomes reach the poles
A new nuclear envelope forms round each new group of chromosomes
What is the name of the process where the cell membrane divides into 2 during cell division?
Cytokinesis
