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.
In the middle of some bones is jelly-like bone marrow, where new cells are constantly being produced for blood, the Merck Manuals noted. Teeth are considered part of the skeletal system but they are not counted as bones. Teeth are made of dentin and enamel, which is strongest substance in your body. Teeth also play a key role in the digestive system. The skeletal system has two distinctive parts: the axial skeleton and the appendicular skeleton, according to the U.S National Library of Medicine (NLM).