Genes are segments of DNA that have code for a specific protein that functions in one or more types of cells. Chromosomes are structures in cells that contain a person's Genes. Genetic disorders can be caused by a mutation in one gene which is called a monogenic disorder.
The fourth one about traits is tricky to decipher as there are about 25 to 35 thousand genes in one cell that carry information inherited from your parents that determine your traits. If Chemical traits could be explained further in detail, this might be an option
