PSYC 100 Lecture Notes - Lecture 32: Twin Study, Melanism, Zygote

• School: McGill University
• Department: Psychology
• Course: PSYC 100
• Professor: Daniel Levitin

Document Summary

Genetics+refers+not+only+to+characteristics,+but+also+to+the+process+involved+in+turning+genes+on+ and+ off. + nature/nurture+ is+ related+ and+ influences+ each+ other. + (2001:+ human+ genome+ project+ whose+1st+task+was+to+map+out+the+entire+structure+of+dna. +we+have+fewer+than+30+000+genes. Chromosomes:+(23+pairs)+structure+within+the+cell+body+made+out+of+genes:+the+unit+of+heredity+ made+ of+ dna+ that+ code+ for+ a+ specific+ protein,+ which+ carries+ a+ specific+ task. + the+ environment+ decides+which+proteins+are+produced+and+when+they+are+produced+ Mendel+ (1866)+ developed+ selective+ breeding+ that+ strictly+ controlled+ which+ plants+ bred+ with+ other+plants. +he+establish+the+basis+of+genetics:+dominant+and+recessive+genes++ Twin+ studies:+ compare+ similarities+ between+ different+ types+ of+ twins+ to+ determine+ the+ genetic+ basis+of+specific+traits. +monozygotic+twins:+result+from+one+zygote+splitting+in+2,+both+having+the+ same+ genetic+ background,+ the+ dna+ is+ not+ perfectly+ the+ same. + dizygotic+ twins:+ 2+ separately+ fertilized+eggs. + Adoption+ studies:+ compare+ the+ similarities+ between+ biological+ relatives+ and+ adoptive+ relatives. + (living+ in+ the+ same+ home+ has+ no+ effect+ or+ very+ little+ on+ behaviour+ however,+ identical+ twins+ raised+together+or+apart+or+very+likely+to+be+similar+ Heritability:+ a+ statistical+ estimate+ of+ the+ variation,+ caused+ by+ differences+ in+ heredity,+ in+ a+ trait+ within+ a+ population. + (if+ within+ a+ population+ a+ trait+ such+ as+ height+ has+ a+ heritability+ of+ 0. 6,+ that+ means+60+percent+of+height+variation+among+individuals+within+that+population+is+hereditary. Neurones+are+the+basic+units+of+the+nervous+system;+they+operate+through+electrical+impulse+and+ communicate+ with+ other+ neurones+ through+ chemical+ signals. + they+ have+ 3+ functions:+ taking+ in+ information+from+neighbouring+neurons+(receptions),+integrating+those+signals+(conduction),+and+ passing+signals+to+other+neurones+(transmission). +