PSYCH 1XX3 Chapter Notes - Chapter 2: Egg Cell, Color Blindness, Haemophilia
Document Summary
From the moment of contraception, when a sperm penetrates the ovum, a new cell called a zygote is formed. 46 chromosomes and 23 chromosomes from each parent. A chromosome is a threadlike structure that is made from dna. The zygote divides at an exponential rate. A parent can produce more than 8 million different combinations which can produce 64 trillion distinct offspring. Monozygotic twins: same sperm and ovum, genetically identical. 22 autosomes which are similar in both sexes, only one chromosome differs, the sex chromosome. A male has 1 y and 1 x chromosome. Male chromosome is the deciding factor of the sex of a child. Phenotype: the expression of an individual"s genotype in terms of observable characteristics. A pattern of inheritance in which the expression of a trait is determined by only one allele. Homozygous: when two genes have the same effect on the phenotype. Heterozygous: when two genes have different effect on the phenotype.
