HomeMerck SeronoContact UsGlossaryReferencesSearchSite Guide
			Concern Treatment Pregnancy Experiences Concern Evaluating Your Fertility Understanding Fertility The Basics of Life DNA Cell Division Sexual Differentiation Anatomy & Function Ovulation Sperm Production Importance of Hormones Maximise Your Fertility Infertility: An Introduction Infertility in Females Infertility in Males Implications of Infertility Questions to Ask Your Doctor		The Basics of Life Humans begin life as a single cell - a fertilised egg cell, or zygote. The nucleus of each of these cells is packed with information coded in the form of deoxyribonucleic acid (DNA) and organised into groups called genes, which are arranged on thread-like structures known as chromosomes.  A human zygote contains 46 chromosomes arranged in 23 pairs. One of each pair comes from the mother and one from the father.  As well as being packed with information, the DNA of the chromosomes also has the ability to copy itself; without this, the cells could not duplicate, nor could they pass on information from one generation to another.
			© 2003-2008 Merck Serono S.A. Please read our Legal Statement. US residents should consult the Serono, Inc. fertility website at www.fertilitylifelines.com Last Updated: 5/6/2008