Your answer would be depressants. Such as alcohol.
A homozygous trait is when both traits are the same size for example it could be AA or aa but not Aa
Lack of physical activity and genetics.
Collagen
is a protein fiber that is found in the matrix that lies outside the bone
cells. Population of these collagen fibers that scattered through the matrix are
embedded in a gel-like ground substance called hyaline cartilage, which
is flexible but avascular and contains no nerves or blood vessels.