Psychology 1000 Chapter Notes - Chapter 12: Preterm Birth, Prenatal Development, Birth Weight

• School: Western University
• Department: Psychology
• Course: Psychology 1000
• Professor: Dr.Mike

Document Summary

Developmental psychology examines changes in biological, physical, psychological, and behavioural processes over age. To accomplish this, developmental psychologists often use special research designs. Cross sectional designs comparing people of different ages at the same point in time. Drawback: different age groups (cohorts) grew up in different periods. Longitudinal designs repeatedly test same cohort as it grows older. Sequential design combines the cross sectional and longitudinal approaches and thus we can repeatedly test several age cohorts as they grow older. A females egg cell and males sperm cell contains 23 chromosomes. At conception, an egg and sperm unite to form a zygote which contains a full set of 23 chromosomes. The 23rd chromosome determines the sex of the baby. Female 23rd pair is an xx chromosome. Male 23rd pair is an xy chromosome. The y chromosome contains a specific gene called the tdf (testis determining factor) gene that triggers male sexual development. This gene initiates development of testes around 6-8 weeks.