Mitosis and meiosis Flashcards
What is mitosis used for?
Asexual reproduction
Growth
Tissue repair
Repair cells
What happened in prophase in mitosis?
- The nuclear envelope and nucleolus breaks down
- The centrioles duplicate and go to opposite poles
- The DNA condenses into 2 identical chromatids
- Spindle fibres made from tubulin are made from the centrioles in animal cells
What happened in metaphase in mitosis?
- The chromatids move into the middle down the equator of the cell or the metaphase plate
- The spindle fibres attach to the centromeres on the chromatids
What happened in anaphase in mitosis?
- The centromere divides and the sister chromosomes are dragged to opposite poles.
What happened in telophase in mitosis?
- A nuclear envelope is made around the chromosomes and they unravel
- The cell membrane starts to split
What happens in cytokinesis after mitosis in animal cells?
The plasma membrane folds inwards and ‘nips in’ the cytoplasm
What is meiosis used for?
Sexual reproduction
What happened in prophase I in meiosis?
- The nuclear envelope and nucleolus breaks down
- The centrioles duplicate and go to opposite poles
- The DNA condenses
- Spindle fibres made from tubulin are made from the centrioles in animal cells
- The homologous pairs of chromosones form bivalents and exhange alleles
What happened in metaphase I in meiosis?
- The homologous pairs of chromosones are opposite to each other on the equator
- The spindle fibres connect to the centromeres of the chromatids
What happened in anaphase I in meiosis?
The homologous chomosones are dragged to the opposite poles by the motor proteins on the tubulin spindle fibres
What happened in telophase I in meiosis in animal cells?
- A nuclear envelope is made around the chromosomes and they unravel
- The cell membrane starts to split into 2 not genetically identical daughter cells with 1/2 the number of chromosomes from the original
What happened in telophase I in meiosis in plant cells?
- A nuclear envelope is made around the chromosomes and they unravel
- The cell membrane starts to split into 2 not genetically identical daughter cells with 1/2 the number of chromosomes from the original
What happens in telophase II in meiosis in plant cells?
- A nuclear envelope is made around the chromosomes and they unravel
- The cell membrane starts to split into a ‘tetrad’ of 4 haploid daughter cells with half the number of chromosomes as the 1st cell
What are the similarities between mitosis and meiosis?
Mitosis and meiosis 2 are similar in what happens
Both have the same interphase
What happens in cytokinesis in plant cells?
An end plate is formed from where the equator of the spindle was, and new plasma membrane and cellulose cell wall are laid down on either side along the end plate