Cell Division Flashcards
What are the main stages of cell division?
Interphase
Mitosis
Cytokenisis
What are the 3 stages of interphase?
G1, S, G2
What happens in each of the stages of interphase?
G1: organelles are duplicated
S: DNA replicated
G2: cell checked for errors and repaired
What is the G0 phase used for?
Specialisation and differentiation
What happens at each check point in the cell cycle?
G1: cell size and nutrients
G2: cell size and DNA
What happens during prophase?
Nuclear envelope breaks down and chromosomes coil up
What happens during metaphase?
Chromosomes allign on the metaphase plate in homologous pairs
What happens during anaphase?
The spindle fibres attached to centromere and contract pulling chromatids to poles
What happens during telophase?
The nuclear envelope re builds
What happens during cytokenisis?
The cytoplasm splits with organelles
What does meiosis create?
Gametes, 4 haploid cells
What does mitosis create?
2 diploid cells
What is crossing over and when does it occur?
When a maternal gene deals with the complementary paternal gene during prophase 1
What is independent assortment and when does it occur?
When the homologous pairs align on metaphase plate randomly during metaphase 1 and 2
Where are stem cells created?
G0
What is potency?
The ability to divide and differentiate
What does totipotent mean?
Can differentiate into any cell, found in zygotes
What does pluripotent mean?
Can form any tissue but not whole organisms, found in embryos
What does multipotent mean?
Can only form cells within certain tissues
Where are stem cells found in plants?
Meristems
What are the 4 types of tissue?
Muscle, nervous, epithelial, connective
What are stem cells used for?
Treatment of diseases
What is the equation for Calculating mitotic index?
MI = ( number of cells with condensed chromosomes ÷ total number of cells ) × 100
What is the equation for Calculating mitotic index?
MI = ( number of cells with condensed chromosomes ÷ total number of cells ) × 100
