This one's a humdinger. A lot of it is compacted because most points are obvious.
3.1 Meiosis
Meiosis is a specialized form of cell division that produces haploid gametes from diploid parents.
Haploid gametes have half the number of chromosomes. Male gametes: sperm and female: ova.
Stages of meiosis composed of two phases. Meiosis 1 and 2 they produce 4 haploid gametes.
Meiosis 1: interphase - chromosomes replicate and form joined sister chromatids.
Prophase - chromosomes shorten and thicken.
Metaphase - homologous chromosomes pair up along the middle
Anaphase- homologous chromosomes separate and move to opposite poles along with their sister chromatids.
Telophase - similar to mitosis
Meiosis 1 results in 2 daughter cells but each has only 1 of the homologous chromosomes with it's ister chromatid still attached.
Meiosis 2: just like mitosis but starts off with 2 daughter cells.
Section 3.2
Fertilization; fusion of gametes.
Sperm + egg = zygote
Zygote receives half of it's chromosomes from each parent. Each new cell will contain the same genome as the zygote.
Different form of same gene - allele.
Dominant: express it's trait if present
Recessive: only expressed if both chromosomes contain the recessive allele
Incomplete dominance: eg red + white = pink.
Codominance: two sets of instructions but randomly picks one.
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