PS275 Chapter Notes - Chapter 3: Egg Cell, Zygote, Epigenetics
Document Summary
Chapter 3 hereditary influences on development: genotype the genes that a person inherits, phenotype a person"s observable or measurable characteristics, epigenetics mechanisms of gene and environment interactions. Growth of the zygote and production of body cells: mitosis process through which the zygote begins to replicate itself, 1. Zygote divides into two cells, then four, eight, sixteen, etc. 223 (8 million +) different genetic combinations in his sperm or ova. How do phenotypes develop through genotypes: three main patterns of genetic inheritance involving single genes: (1) simple dominant-recessive inheritance (2) codominance (3) sex-linked inheritance, simple dominant-recessive inheritance. Instead, the observable traits follow a pattern of continuous variation, with few people having the traits in the middle of the distribution (traits follow a normal bell curve distribution) Found that prenatal maternal hardship directly affected the genes and functions of their offspring. Hereditary disorders: congenital defects a problem that is present (though not necessarily apparent) at birth.
