Español
PrintEmail
Decrease (-) Restore Default Increase (+)
Health Info

Health Info


Chromosomes and DNA
Chromosomes and DNA


Chromosome

Definition:

Chromosomes are structures found in the center (nucleus) of cells that carry long pieces of DNA. DNA is the material that holds genes . It is the building block of the human body.

Chromosomes also contain proteins that help DNA exist in the proper form.



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 gives an X chromosome to the child. The father may contribute an X or a Y. It is the chromosome from the father that determines if the baby is a girl or a boy.

The remaining chromosomes are called autosomal chromosomes. They are known as chromosome pairs 1 through 22.



References:

Stein CK. Applications of Cytogenetics in Modern Pathology. In: McPherson RA, Pincus MR, eds.Henry's Clinical Diagnosis and Management by Laboratory Methods. 22nd ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 68.




Review Date: 1/13/2013
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by A.D.A.M. Health Solutions, Ebix, Inc., Editorial Team: David Zieve, MD, MHA, David R. Eltz, Stephanie Slon, and Nissi Wang.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
adam.com


Online Tools

Locations

Helpful Info

Links