The flashcards below were created by user
on FreezingBlue Flashcards.
What creates variation?
- Crossing over in Prophase I
- Independent assortment in Metaphase I
- which egg? Cell makes 1 egg and 2 polar bodies
- Which sperm? Fertilization is a random event
- primary spermatocyte makes 4 sperm
- during fetal development, stops at prophase I
- with each cycle starting with puberty
- I completes prior to ovulation
- ovulation and fertilization, meiosis II completes
- 1 egg and 2 polar bodies…variation
2 cell divisions in Meiosis
What happens during Meiosis I?
Homologous pairs separate
What happens during Meiosis II?
Sister chromatids separate, producing 4 daughter cells, each haploid (1n)
Having one of each type of chromosome characteristic of the species.
Stages of Meiosis I
- Prophase I
- Metaphase I
- Anaphase I
- Telophase I
Process in which homologous chromosomes exchange corresponding segments during prophase I of meiosis.
- chromosomes pair up, called synapsis
- pairs line up along the cell’s equator (middle)
•Independent assortment occurs
- pairs separate (apart)
- towards opposite ends of the cell
Period between Meiosis I and Meiosis II
Same thing happens as in Meiosis I: Prophase II, Metaphase II, Anaphase II, Telophase II--DNA isn't replicated so the end result is haploid cells
What does mitosis NOT have?
- NO homologous pairs
- NO crossing over
- NO independent assortment
What does mitosis have?
- Sisters separate
- ONE division
- 2 diploid daughters
What does meiosis have?
- Homologus pairs
- Crossing over
- Independent assortment
- Homologs and sister chromatids separate
- 2 divisions
- 4 haploid daughters