6.3 Meiosis Flashcards
What us meiosis known as
Reduction division
What are teh chromosomes called in each nucleus
Contain homologous chromosomes
Termed diploid
2 chromosomes of each type
What’s an allele
Different versions of the same gene
All have the same locus on the chromosome
What is meiosis 1
Reduction division
Pair of homologous chromosomes separate
Each cell will only contain 1 full set of genes so they are haploid
What happens in meiosis 2
Similar to mitosis
Pairs of chromatids in each daughter cell are separated
Forming 4 daughter cells
Meiosis 1
Prophase
Homologous chromosomes pair up forming bivalents
Chromatids entangle so crossing over takes place
Meiosis 1
Metaphase 1
Homologous chromosomes pair up along the metaphase plate
Orientation of chromosomes is random which is called independent assortment leading to genetic variation
Meiosis 1
Anaphase 1
Whole Homologous chromosomes are pulled to opposite parts of cell so chromatids stay joined
What are the points at which chromatids break and rejoin called
Chiasmata
What’s formed when exchange between sister chromatids occurs
Recombinant chromatids
Genes have been exchanged
Causing genetic variation
Meiosis 1
Telophase 1
Same as mitosis
Meiosis 2
Prophase
Chromosome consist of 2 chromatids
They condense and become visible
Spindle formation begins
Meiosis 2
Metaphase
Individual chromosomes on metaphase plate
More independent assortment
Cytokinesis in meiosis 2
Form 4 daughter cells
Haploid cells due to reduction division
Genetically different
