The Punnett square shows the possible genotype combinations of two parents who are heterozygous for a particular trait.
What is the probability of the parents having a child who is homozygous dominant for this trait?

0%
25%
50%
75%

25%

Explanation:

The child only comes out as homozygous dominant (YY) for the trait in 1/4 boxes in the Punnett Square. This translates to the child having a 25% chance of being homozygous dominant for the trait.

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what do the different brain waves do?

explanation:

brainwaves are produced by synchronised electrical pulses from masses of neurons communicating with each other. brainwaves are detected using sensors placed on the scalp. brainwave speed is measured in hertz (cycles per second) and they are divided into bands delineating slow, moderate, and fast waves.