PSYCH 2AA3 Chapter Notes - Chapter 2: Heritability, Xyy Syndrome, Zygosity
10 Dec 2014
School
Department
Course
Professor
Document Summary
Chapter 2 genetic bases of child development. 2. 1 mechanisms of heredity: biology of heredity, chromosomes structures containing genetic material. Each made up of one dna molecule. Zygote, combined sperm and egg, contains 46. Autosomes first 22 pairs, each about same size. Sex chromosomes 23 pair, determines sex of child: gene set of biochemical instructions provided by nucleotide bases. Genotype complete set of genetic instructions making up one"s heredity. Phenotype genotype with environmental influences producing one"s features: single gene inheritance, alleles different forms of genes. Homozygous when allele pairs are the same. Heterozygous when allele pairs are different: dominant vs. recessive. Homozygous recessive child inherits recessive alleles from both parents: sickle-cell disease, albinism, cystic fibrosis, phenylketonuria, tay-sachs. Homozygous dominant very rare: huntington"s disease, abnormal chromosome number. 4 dominant and 4 recessive (common: methods, twin studies. Monozygotic/identical twins single fertilized egg that splits in two about all of same genes. Dizygotic/fraternal twins two separate fertilized eggs about half of same genes.
