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Name: Kristi
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Question:
The dominant characteristic is the one most likely to appear in the offspring. In human beings, brown is the dominant color for eyes. The children who inherit at least on dominant gene will have either brown, green, or hazel eyes. Only childten who inherit two recessive genes will have pure blue eyes. If there are eight children in the family, what color eyes will most of them have?



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http://www.newton.dep.anl.gov/archive.htm


Search under eye color

Steve Sample


You answer is of course dependent on the genes of the parents. If both parents do not have the recessive gene, then no children will have light colored eyes. If one has a recessive gene and the other not, then still no children will have light color eyes and on the average 25% of the eight children could have the recessive gene. If both parents have the recessive gene, then 25% of the eight children could have light color eyes.

Dr. Myron


Remember that Punnett squares only determine PROBABILITY not actual outcome. We all know families that have all boys or all girls even though odds are that there will 50% of each. In the model you are using, there should be 75% brown eyes and 25% blue. However, eye color is now believed to be polygenic, or under the control of more than one gene. So if you inherit blue eyes, what COLOR blue are they?

Van Hoeck



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