PSYC 2076 Lecture Notes - Fetus, Teratology, Thalidomide
Document Summary
Chapter 3 the start of life: genetics and prenatal development. Genes basic units of genetic information that are composed of dna molecules. Genes are arranged into groups, along 46 chromosomes in 23 pairs. Human cells contain 23 pairs of chromosomes for a total of 46. There are 22 pairs of autosomes and one pair of sex chromosomes. The sex chromosomes are the x chromosome and the y chromosome. The male gametes or sperm cells in humans and other mammals are heterogametic . The female gametes or eggs however, contain only the x sex chromosome and are homogamatic. The sperm cell determines the sex of an individual in this case. If a sperm cell containing an x chromosome fertilizes an egg, the resulting zygote will be xx or female. If the sperm cell contains a y chromosome, then the resulting zygote will be. This is much more common in animals than in people.
