======Dominance and Recessiveness with Food Coloring======


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**Alternative titles:** Genetics with Food Coloring
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====Summary====                   
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====Procedure====  
  - Fill two small glasses with red-colored water and two more with plain water.  
  - Show three empty large glasses to the class (one should secretly contain 1 mL of bleach).  
  - Pour the two red glasses into the first large glass—result: red phenotype (homozygous red).  
  - Pour the two clear glasses into the second large glass—result: clear phenotype (homozygous clear).  
  - Pour one red glass and one clear glass into the third glass (with bleach)—result: clear solution, representing a heterozygote where the clear trait is dominant.  
  - For codominance, prepare one small glass with red water and another with yellow water.  
  - Pour them together into a large glass—result: orange solution, representing codominance or blending inheritance.



====Links====
📄 DOMINANCE AND RECESSIVNESS (Page 10) - Shannon Winter: [[https://www.unco.edu/nhs/science/pdf/demos/2006_CSC.pdf]]\\


====Variations==== 
  * Expand the analogy by creating Punnett squares and comparing predicted vs. observed “phenotypes.”



====Safety Precautions====
  * Handle bleach carefully—only use a very small amount (1 mL) and keep away from skin, eyes, and clothing.  
  * Clearly label the bleach-containing glass before setup to avoid accidents.  
  * Wear safety glasses and gloves if handling bleach directly.  
  * Dispose of bleach solutions safely by diluting with plenty of water before discarding.




====Questions to Consider====
  * Why does the clear water represent the dominant trait in this analogy? (Because it masks the presence of the red when combined with bleach.)  
  * How is codominance represented in the red and yellow mixture? (Neither color dominates, and both traits are visible as a blended orange.)  
  * What is the difference between dominance and codominance in genetics? (Dominance means one allele masks the other, while codominance means both alleles are expressed together.)  
  * How does this demonstration simplify the real complexity of genetics? (It uses visible color mixing as an analogy, but real genetic dominance involves proteins and biochemical pathways.)