ANT211H5 Lecture Notes - Lecture 2: Ontogeny, Egg Cell, Sex Organ
Document Summary
Usually once growth and development is completed, then organism has reached sexual maturity. Sociobiologists cannot ignore analyses of the learning process: behaviour is dependent on environment we have to have a good understanding of environmental settings (can be internal/cellular and external) Sperm is enveloped into egg"s cytoplasm: sperm has low levels of cytoplasm whereas ovum has a high levels of cytoplasm, ovum undergoes 2nd meiotic division, male & female pronuclei grow (12 hours, nuclei unite = zygote. Implantation in the uterine wall: then the nuclei will begin to multiple so that every cell will have a full complement of dna, trophoblast cells the cells that form for the amnion sac, blastocyte. It is the cellular environment that determine which chromosomes are turned on to specific actions which can allow them to have different functions of the body. The potential of cells to change their original function: often wanes or disappears as differentiation progresses.
