LIFE 120 Lecture Notes - Lecture 20: Sister Chromatids, Cell Division, Bone Marrow
Document Summary
Life120 chapter 9 lecture (10/12/16) with clicker questions in red. In unicellular organisms, division of one cell reproduces the entire organism. Development, growth, and repair: cell division enables multicellular eukaryotes to develop from a single cell. Joining of gametes introduces two genomes to make one new organism: once fully grown, multicellular eukaryotes need cell division to renew, repair, or replace cells as needed. Cells of body cells called somatic cells skin or muscle cells. Can be very bad if cells are mutated (aged, cancer, etc. ) and reproduce. Dna is passed from one generation of cells to the next with remarkable fidelity. Makes (cid:374)e(cid:449) (cid:272)ells, keeps the(cid:373) (cid:862)fresh(cid:863: meiosis. Meiosis yields non-identical daughter cells that have only one set of chromosomes, half as many as the parent cell. Dna, chromosome, genome: dna molecules in a cell are packaged into chromosomes, all the dna i(cid:374) a (cid:272)ell (cid:272)o(cid:374)stitutes the (cid:272)ell"s ge(cid:374)o(cid:373)e. In mitochondria: prokaryotes (bacteria)-single circular dna molecule, eukaryotes-multiple chromosomes.
