From there the Missouri flows east and southeast, ultimately joining the Mississippi River about 10 miles (16 kilometers) north of St. Louis, Missouri. The Missouri River flows through Montana, North Dakota, South Dakota, Nebraska, Iowa, Kansas, and Missouri.
Chromosome theory of inheritance. generalization that genes are located on chromosomes and that the behavior of chromosomes during meiosis and fertilization accounts for inheritance patterns, also states that mendelian genes have specific loci, chromosomes undergo segregation and independent assortment.
Genes, which are made up of DNA, act as instructions to make molecules called proteins. In humans, genes vary in size from a few hundred DNA bases to more than 2 million bases. The Human Genome Project has estimated that humans have between 20,000 and 25,000 genes.lthough most DNA is packaged in chromosomes within the nucleus, mitochondria also have a small amount of their own DNA. This genetic material is known as mitochondrial DNA or mtDNA. Mitochondria (illustration) are structures within cells that convert the energy from food into a form that cells can use.