Monohybrid Cross/Dihybrid Crosses

Monohybrid- one trait
For example: Red Plant x Green Plant
These can be expressed in simple punnet squares with four squares:

A- dominant for tall a- recessive for short
Green Plant (Aa) x Green Plant (Aa)

external image punnet_square.gif
*What percentage of the offspring will be red?

Dihybrid- two traits
For example: Tall Green Plant x Short Green Plant
These can be expressed in punnet squares containing sixteen squares:

Y- dominant for tall y- recessive for short
R- dominant for green r- recessive for red
Tall Green Plant (YyRr) x Tall Green Plant (YyRr)
external image dipunnet.gif
What percentage of the offspring is tall and red?

Monohybrid: 25%
Dihybrid: 25%