PSYC 2000 Lecture Notes - Lecture 13: Ploidy, Asexual Reproduction, Paramecium
Document Summary
Mom"s egg and dad"s sperm (both 1n - haploid = 23 chromosomes , 23rd is x or y for sperm, x for egg) Fertilized creates 2n - diploid = 46 chromosomes. Cell cycle - one cell -> two cells -> four cells -> eight cells Genetically identical, maybe a few mistakes, nothing major. If we split clump of cells into two parts, each clump keeps dividing to form two embryos, creates identical twins. Cells communicate which genes to turn on to become different tissues/ cells for different functions- diff organ systems. Biologically our cycle ends when we reproduce. Male and female egg and sperm combined by fertilization. Cycle begins at birth and ends at birth. Sex cells formed from preexisting diploid cells. Pollen - two haploid sperm cells in each pollen grain. Important for haploid to be haploid because they combine to create diploid. Chromosomes inside membrane bound nucleus in eukaryotes. Chromosomes consist of genes, genes consist of dna.
