PSY 2105 Lecture Notes - Lecture 4: Umbilical Cord, Placenta, Amniotic Sac

• School: University of Ottawa
• Department: Psychology
• Course: PSY 2105
• Professor: Caroline Sullivan

Document Summary

All living things are composed of cells, we have over 10 trillion of them. Heart of the cell = nucleus, inside of which lies our genetic material, our dna. Dna is organized into chemical strands called chromosomes: which store and transmit genetic information. Female characteristics but don"t turn into females at puberty. Determines sex of the baby (xx = female, xy = male) Autosomes: the 22 pairs of chromosomes that are not sex chromosomes. Two zygotes or fertilized ova: more common (40% male-female, genetic: disposition to release two eggs, usually seen with ivf. Identical/monozygotic: one zygote that divides into two individuals. The location of genes on the chromosomes is very important. For each pair of chromosomes, the genes for the same trait (e. g. eye colour) are in the same locations and are called alleles. One allele is inherited from each parent. The 2 alleles are not always the same, so many different combinations of characteristics can result.