ANTH 101 Lecture Notes - Lecture 5: Dna Replication, Nuclear Membrane, Archaea
Document Summary
Prokaryotes: one celled organisms: bacteria & archea, simple cell structure, first organisms 3. 7 billion years ago (bya, no nuclear envelope/nucleus. Eukaryotes: multi-celled organisms: complex cell structure, 1. 5 bya, has a nucleus, many more organelles, mitochondria: responsible for producing energy. Has separate dna called mitochondrial dna, passed down through mother. Lasts long than normal dna: two types of cells. Somatic cell (body or diploid cells): full set of 46 chromosomes. Gamete cell (sex or haploid cells): half set of 23 chromosomes: cell division. Mitosis somatic production: prophase: dna duplication has resulted in chromosome replication. Nuclear membrane disappears, centrosomes position themselves: metaphase: chromosomes align themselves down the center of the cell. Centrosomes attach to chromosomes to prepare to separate them: anaphase: duplicated chromosomes are separated to opposite ends of cell, telophase: cells begin to separate, new components formed. Nucleus structures are formed around sets of chromosomes: cytokinesis: stage after mitosis where cells completely divide.
