DNA

Definition

DNA, or deoxyribonucleic acid, is the hereditary material in all living organisms and many viruses, consisting of two long strands forming a double helix. This molecule carries genetic information essential for the growth, development, functioning, and reproduction of organisms, serving as a blueprint for the synthesis of proteins and regulation of cellular processes.

5 Must Know Facts For Your Next Test

1. DNA is composed of four nucleotide bases: adenine (A), thymine (T), cytosine (C), and guanine (G), which pair specifically (A with T and C with G) to form the double helix structure.
2. The sequence of these nucleotide bases encodes genetic information that determines an organism's traits and functions.
3. DNA replication is a critical process that occurs before cell division, ensuring that each new cell receives an exact copy of the DNA.
4. Mutations in DNA can lead to changes in the protein produced, potentially resulting in diseases or altered traits in an organism.
5. DNA is not only found in the nucleus of eukaryotic cells but also in mitochondria and plastids; prokaryotic cells contain DNA in a simpler form within their cytoplasm.

Review Questions

• How does the structure of DNA relate to its function in storing genetic information?
  • The structure of DNA as a double helix is crucial for its function in storing genetic information. The two strands allow for complementary base pairing between the nucleotides, which helps maintain the integrity of the genetic code during replication. Additionally, the specific sequence of nucleotide bases along the DNA strands encodes the instructions for building proteins, ultimately determining an organism's traits.
• Discuss the implications of mutations in DNA and how they can affect metabolic processes in an organism.
  • Mutations in DNA can lead to changes in amino acid sequences during protein synthesis, which may alter the function or stability of enzymes involved in metabolic processes. For example, a mutation that affects an enzyme's active site could inhibit its ability to catalyze a reaction efficiently. This disruption can result in metabolic disorders or altered pathways that affect energy production or nutrient utilization within the organism.
• Evaluate the significance of understanding DNA structure and function for advancements in metabolomics and systems biology.
  • Understanding DNA structure and function is vital for advancements in metabolomics and systems biology because it provides insights into how genetic variations influence metabolic pathways. By studying how genes encode enzymes and regulatory proteins involved in metabolism, researchers can identify relationships between genotype and phenotype. This knowledge aids in developing targeted therapies for metabolic diseases and enhances our comprehension of complex biological systems by integrating genetic information with metabolite profiles.

Related terms

RNA:

RNA, or ribonucleic acid, is a molecule essential for coding, decoding, regulation, and expression of genes. Unlike DNA, RNA is usually single-stranded and plays key roles in protein synthesis.

Nucleotide: Nucleotides are the building blocks of DNA and RNA, consisting of a sugar, a phosphate group, and a nitrogenous base. In DNA, the four bases are adenine, thymine, cytosine, and guanine.

Chromosome: Chromosomes are long strands of DNA wrapped around proteins called histones that organize and condense the genetic material within the cell nucleus. Humans typically have 23 pairs of chromosomes.