Each gene has a specific location (locus) on a chromosome and may come in several forms (alleles). genotype The actual genes for a trait present in an individual. genotypic ratio The expected numbers of different genotypes produced by a particular cross.
Bones are made from calcium. A typical bone has an outer layer of hard or compact bone, which is very strong, dense and tough. Inside this is a layer of spongy bone, which is â¦ like honeycomb, lighter and slightly flexible.
Almost every bone in your body is made of the same materials: 1  The outer surface of bone is called the periosteum (say: pare-ee-OSS-tee-um). 2  The next layer is made up of compact bone. 3  Within the compact bone are many layers of cancellous (say: KAN-sell-us) bone, which looks a bit like a sponge.