Ask A Scientist© Zoology Archive

 
name        Bronwyn
status      student
age         16

Question -  When using Punnet Square, if a trait is homozygous how do 
 you know to use 2 capital letters, or 2 lower case letters?
There are no real set rules on this.  Usually, homozygous recessive are 
lower case and dominant is upper.  Co-dominant are usually expressed as 
upper case as well.

Steve Sample
York High School
Elmhurst, Illinois
60126
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