Health Encyclopedia
Home | List of Topics | Genetics | Medical Genetics
Chromosome
Definition
Chromosomes are long pieces of DNA found in the center (nucleus) of cells. DNA is the material that holds genes. It is considered the building block of the human body.
Information
Chromosomes come in pairs. Normally, each cell in the human body has 23 pairs of chromosomes (46 total chromosomes). Half come from the mother; the other half come from the father.
Two of the chromosomes (the X and the Y chromosome) determine if you are born a boy or a girl (your gender). They are called sex chromosomes:
- Females have 2 X chromosomes.
- Males have 1 X and 1 Y chromosome.
The mother always contributes an X chromosome to the child. The father may contribute an X or a Y. Therefore, it is the father that determines the gender of the child.
The remaining chromosomes are called autosomal chromosomes. They are known as chromosome pairs 1 through 22.
Related topics:
- Autosomal dominant
- Autosomal recessive
- Genetic counseling and prenatal diagnosis
- Sex-linked dominant
- Sex-linked recessive
For detailed information, see heredity and disease (genetics).
Review Date:1/16/2007
Reviewed By:Brian Kirmse, MD, Mount Sinai School of Medicine, Department of Human Genetics, New York, NY. Review provided by VeriMed Healthcare Network.
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is the first of its kind, requiring compliance with 53 standards of quality and accountability, verified by independent audit. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial process. A.D.A.M. is also a founding member of Hi-Ethics (www.hiethics.com) and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).
The Agency for Health Care Administration (Agency) and this website do not claim the information on, or referred to by, this site is error free. This site may include links to websites of other government agencies or private groups. Our Agency and this website do not control such sites and are not responsible for their content. Reference to or links to any other group, product, service, or information does not mean our Agency or this website approves of that group, product, service, or information.
Additionally, while health information provided through this website may be a valuable resource for the public, it is not designed to offer medical advice. Talk with your doctor about medical care questions you may have.
Help for Florida Consumers.
- Brochures and Guides
- Compare Drug Prices
- Compare Hospitals and Ambulatory Surgery Centers (Updated – 2007 data)
- Emergency Department Care
- File a Complaint
- Find Doctors & Pharmacies that e-Prescribe
- Find Facilities
- Find Health Care Professionals
- Florida Medicaid Information
- Health Plans
- Look up a Medical Condition
- Medical Help Resources
- Other Health Links
- Senior Health
- Symptom Navigator
