This 31-slide powerpoint presentation covers 'Topic 3.3 - Meiosis' in the 2016 IB Biology curriculum. Each slide includes the specific learning objective as well as key vocabulary that students should note. The topic has been divided into three sections:
A - Meiosis Intro
B - Stages of Meiosis
C - Genetic Variation & Non-disjunction
The presentation itself contains minimal information as it is intended to be used with teacher guidance. They are also formatted to be visually pleasing and to print well for handouts or revision. Please see the preview file for an idea of the slide aesthetic and level of detail.
As always, please let me know if you have any suggestions for improvements. These are always a work in progress!
U1: One diploid nucleus divides by meiosis to produce four haploid nuclei.
U2: The halving of the chromosome number allows a sexual life cycle with fusion of gametes.
U3: DNA is replicated before meiosis so that all chromosomes consist of two sister chromatids.
U4: The early stages of meiosis involve pairing of homologous chromosomes and crossing over followed by condensation.
U5: Orientation of pairs of homologous chromosomes prior to separation is random.
U6: Separation of pairs of homologous chromosomes in the first division of meiosis halves the chromosome number.
U7: Crossing over and random orientation promotes genetic variation.
U8: Fusion of gametes from different parents promotes genetic variation.
A1: Non-disjunction can cause Down syndrome and other chromosome abnormalities.
A2: Studies showing age of parents influences chances of nondisjunction.
A3: Description of methods used to obtain cells for karyotype analysis e.g. chorionic villus sampling and amniocentesis and the associated risks.
S1: Drawing diagrams to show the stages of meiosis resulting in the formation of four haploid cells.