PSYC3313 Lecture Notes - Lecture 2: Chromosome Abnormality, Y Chromosome, Gene Expression
Document Summary
Humans have 23 pairs of chromosomes, 2 of which are sex linked where xx = girl and xy = boy. Chromosomes are made up of 2 twisted strands of dna. Regulator genes control the activity of other genes. Effects of certain genes add up to influence the phenotype, e. g. height, skin colour. Dominant is more influential than recessive gene e. g. hair colour. Aa has a value of 3, aa has a value of 2 and aa 1. X linked recessive gene almost never counterpart on y chromosome. X linked recessive genes affect phenotype of boys more than girls. Genes for many allergies, diseases, learning issues are x linked. Down syndrome, klein fetter syndrome, turner syndrome. A given genotype will develop differently in different environments. Children are active creators of the environment in which they live. Select environments to match their own interests. Environments can alter functioning of genetics through gene expression.