information from parent to offspring. It was known early into the 20th century that chromosomes, the

material of cells, contained DNA. In 1944, Oswald T. Avery, Colin M. MacLeod, and Maclyn McCarty

concluded that DNA was the basic genetic component of chromosomes. Later, RNA would be proven to

regulate protein synthesis. (Miller, 139)

DNA is the genetic material found in most viruses and in all cellular organisms. Some viruses do not have

DNA, but contain RNA instead. Depending on the organism, most DNA is found within a single chromosome

like bacteria, or in several chromosomes like most other living things. (Heath, 110) DNA can also be

outside of chromosomes. It can be found in cell organelles such as plasmids in bacteria, also in

plants, and mitochondria in plants and animals.

All DNA molecules contain a set of linked units called nucleotides. Each nucleotide is composed of three

things. The first is a sugar called deoxyribose. Attached to one end of the sugar is a phosphate group,

the other is one of several nitrogenous bases. DNA contains four nitrogenous bases. The first two,

Hole, John W., Jr. Essentials. Dubuque, Iowa: Wm. C. Brown Company Publishers, 1983.

compounds of uracil and cytosine. (Miller, 146)

For transcription to take place, the RNA polymerase enzyme is needed first separate the two strands of

compounds. (Miller, 141) Four types of DNA nucleotides can be formed, depending on which nitrogenous

Mader, Sylvia S. Inquiry Into Life. New York: Wm. C. Brown Company Publishers, 1988.

Some common words found in the essay are:
Grolier Encyclopedia, DNA RNA, Methods Materials, Maclyn McCarty, Watson Crick, DNA Deoxyribonucleic, DNA's RNA, Francis Crick, protein synthesis, Company Publishers, nitrogenous bases, dna rna, double helix, amino acids, hydrogen bonds, mrna molecule, genetic material, bases dna, sugar phosphate, Foresman Company, grolier encyclopedia 1992, single-ringed pyrimidine compounds, base pairing miller, strands double helix, wm brown company,
Approximate Word count = 1313
Approximate Pages = 5 (250 words per page double spaced)