A dominant trait can be shown both when an organism is homozygous dominant AND heterozygous. Two different genotypes give the same visible result so a testcross is needed to be able to accurately say if the organism is homozygous dominant or heterozygous
An enzyme is a substance produced by a living organism that acts as a catalyst to bring about a specific biochemical reaction. nucleus.
Answer: skeletal system
Explanation: osteoarthritis affects the cartilages of Bones.cartilages is a flexible connective tissue ,in a joint that covers the surface of the bones in the joint.it also cushions the bones from impact.
During osteoarthritis,the cartilages wears out and causes the bones in the joint to rub against each other causing swollen joints, painful joints and stiffness of joints
It occurs in joints of the knees,hips,fingers and toes.