PSYCO104 Lecture Notes - Lecture 4: Twin, Amniote, Twin Study

• School: University of Alberta
• Department: Psychology
• Course: PSYCO104
• Professor: Michele Moscicki

Document Summary

The nervous system is the first major bodily system to form in the embryo (3 weeks) At 4 weeks the 3 major levels of the brain are visible. At 7 weeks, the cerebral hemispheres form. Fissures develop in mid-pregnancy (folds and valleys) The simplest animals have sensory and motor neurons. The first neurons appeared in simple invertebrates. Tracts forming a spinal cord emerge from these head neurons. First 22 pairs = development of body and brain. Genes that lead to human brains evolved faster than other species. 50% identical to each parent (and each sibling) Mz (monozygotic/identical) twins = 100% identical genes. Dz (dizygotic/fraternal) twins = 50% identical genes. Genes see the range for a trait, the environment sets the level within the range. Phenotype: how the dna is expressed (ie: blue eyes) Generic matter is psychopathology for two reasons: many genes contribute to increased vulnerability to some disorders.