What is the expected phenotypic ratio for feather colour if two chickens with blue feathers are crossed

The correct answer is - 1:2:1 for black : blue : white chicken.

Explanation:

We know that color of the feather is a trait of the chicken that shows the codominance type of inheritance pattern where both forms of the trait are dominant and make a mix of the forms. In this case, blue is heterozygous BW and black BB and white is WW, then crossed between BW with BW

gametes: B, W and B, W

Punnett

           B       W

B        BB      BW

W        BW     WW

thus, the phenotypic ration is - 1 black : 2 blue : 1 white

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.