Biology Module 2 - 2.mitotic and meiotic cell division 2.8 describe how meiosis contributes to heritable variation

2.8 describe how meiosis contributes to heritable variation

• crossing over  - homologous chromosome pair along their                           length gene  by gene.                                                      - Breaks occur along the                                                      chromosomes and they rejoin trading                                some of their genes

NB crossing over occurs in prophase I

Biology Module 2 - 2.mitotic and meiotic cell division 2.6 describe with the aid of diagrams the process involved in meiotic and cell division

 2.6 describe with the aid of diagrams the process involved in meiotic and cell division

Meiosis has 2 division
I - homologous chromosome separate
II - chromatids separate

diagram of meiosis

source

Meiosis I 

Prophase I - chromosome condense

                  - crossing over 

                  - homologous chromosome pair up

Biology Module 2 - 2.mitotic and meiotic cell division 2.5 explain what is meant by homologous pairs of chromosomes and the term haploid and diploid

2.5 explain what is meant by homologous pairs of chromosomes and the term haploid and diploid


homologous pairs of chromosome - a pair of chromosome that have the same shape, same position of the centromere and the same genes in the sequence

Biology Module 2 - 2.mitotic and meiotic cell division 2.4 discuss the role and importance of mitosis in growth, repair and asexual reproduction

2.4 discuss the role and importance of mitosis in growth, repair and asexual reproduction


Growth - zygote divides repeatedly by mitosis                                        for embryonic development. so important for                            the continuity of life
            - meristems
            - important for the growth of plants




Tissue repair - tissue that is cut divides by mitosis to produce                         new genetically identical cells that cover                                   wounds and join cut edges together  


Asexual reproduction - organism divides by mitosis to                                                  produce genetically identical oganism

Biology Module 2 - 2.mitotic and meiotic cell division 2.3 explain the importance of DNA replication for maintaining gentic stablity

2.3 explain the importance of DNA replication for maintaining genetic stability



Replication involves the complete copying of the entire gene in a cell. 

Replication must occur before mitosis can take place. Mitosis is the type of nuclear division that allows for genetic stability since the nuclei produced are identical to

Biology Module 2 - 2.mitotic and meiotic cell division 2.1 describe with the aid of diagrams the processes involved in mitotic cell division

2.1 describe with the aid of diagrams the processes involved in mitotic cell division

diagram of process of mitotic division

source

Stages of mitosis