DNA

Definition

DNA (Deoxyribonucleic Acid) is the hereditary material in almost all living organisms, carrying genetic information essential for growth, development, and reproduction. It consists of two strands forming a double helix structure.

5 Must Know Facts For Your Next Test

1. DNA is composed of nucleotides, each containing a phosphate group, a sugar molecule (deoxyribose), and one of four nitrogenous bases: adenine (A), thymine (T), cytosine (C), or guanine (G).
2. The pairing rule of DNA bases is A with T and C with G, held together by hydrogen bonds.
3. DNA replication is semi-conservative, meaning each new DNA molecule consists of one old strand and one newly synthesized strand.
4. Enzymes like DNA polymerase play critical roles in the replication process by adding nucleotides to the growing DNA strand.
5. Mutations in DNA can lead to genetic disorders or contribute to the evolution of species through changes in genetic information.

Review Questions

• What components make up a nucleotide in DNA?
• Explain the base-pairing rule in DNA.
• Describe what is meant by 'semi-conservative' replication.

Related terms

RNA:

Ribonucleic acid that plays various roles including acting as a messenger between DNA and protein synthesis machinery.

Genomes: Complete set of genes or genetic material present in a cell or organism.

DNA Polymerase:

An enzyme that synthesizes new strands of DNA complementary to the original template strands during replication.