Test cross
Test Cross
A Test Cross is a genetic technique used to determine the genotype of an organism. This method is particularly useful when the organism exhibits a dominant phenotype, making it difficult to determine whether it is homozygous dominant (AA) or heterozygous (Aa).
Overview[edit | edit source]
The test cross was first introduced by Gregor Mendel, the father of modern genetics. Mendel used this technique in his experiments with pea plants, which led to the discovery of the fundamental laws of inheritance.
In a test cross, the organism in question is crossed with an organism that is homozygous recessive for the trait in question. The resulting offspring's phenotypes are then observed. If any of the offspring display the recessive phenotype, it can be concluded that the parent in question is heterozygous. If all offspring display the dominant phenotype, the parent is likely homozygous dominant.
Procedure[edit | edit source]
The procedure for a test cross involves the following steps:
- Identify the organism whose genotype is to be determined.
- Cross the organism with another organism that is homozygous recessive for the trait in question.
- Observe the phenotypes of the resulting offspring.
- If any of the offspring display the recessive phenotype, the parent in question is heterozygous. If all offspring display the dominant phenotype, the parent is likely homozygous dominant.
Applications[edit | edit source]
Test crosses have a wide range of applications in genetics. They are used in plant breeding and animal breeding to determine the genotype of potential breeding stock. They are also used in genetic research to study the inheritance patterns of specific traits.
Limitations[edit | edit source]
While test crosses are a powerful tool in genetics, they do have some limitations. They can only be used to determine the genotype of an organism for a single trait at a time. Additionally, they require the availability of a homozygous recessive organism for the trait in question, which may not always be possible.
See Also[edit | edit source]
Search WikiMD
Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro / Zepbound) available.
Advertise on WikiMD
WikiMD's Wellness Encyclopedia |
Let Food Be Thy Medicine Medicine Thy Food - Hippocrates |
Translate this page: - East Asian
中文,
日本,
한국어,
South Asian
हिन्दी,
தமிழ்,
తెలుగు,
Urdu,
ಕನ್ನಡ,
Southeast Asian
Indonesian,
Vietnamese,
Thai,
မြန်မာဘာသာ,
বাংলা
European
español,
Deutsch,
français,
Greek,
português do Brasil,
polski,
română,
русский,
Nederlands,
norsk,
svenska,
suomi,
Italian
Middle Eastern & African
عربى,
Turkish,
Persian,
Hebrew,
Afrikaans,
isiZulu,
Kiswahili,
Other
Bulgarian,
Hungarian,
Czech,
Swedish,
മലയാളം,
मराठी,
ਪੰਜਾਬੀ,
ગુજરાતી,
Portuguese,
Ukrainian
Medical Disclaimer: WikiMD is not a substitute for professional medical advice. The information on WikiMD is provided as an information resource only, may be incorrect, outdated or misleading, and is not to be used or relied on for any diagnostic or treatment purposes. Please consult your health care provider before making any healthcare decisions or for guidance about a specific medical condition. WikiMD expressly disclaims responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site. By visiting this site you agree to the foregoing terms and conditions, which may from time to time be changed or supplemented by WikiMD. If you do not agree to the foregoing terms and conditions, you should not enter or use this site. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.
Contributors: Prab R. Tumpati, MD