DNA

Definition

DNA, or deoxyribonucleic acid, is the fundamental genetic material that carries the instructions for the development and function of living organisms. It is the blueprint that guides the growth, reproduction, and characteristics of all life forms.

5 Must Know Facts For Your Next Test

1. DNA is responsible for the storage and transmission of genetic information from one generation to the next.
2. The sequence of the four DNA bases (adenine, thymine, cytosine, and guanine) encodes the genetic instructions that determine an organism's characteristics.
3. DNA replication is the process by which DNA makes an exact copy of itself, ensuring the accurate transmission of genetic information during cell division.
4. Mutations in the DNA sequence can lead to changes in the genetic code, potentially causing alterations in an organism's traits or the development of diseases.
5. DNA plays a crucial role in the regulation of gene expression, controlling the synthesis of proteins that are essential for cellular function and development.

Review Questions

• Explain how the structure of DNA is related to its function in storing and transmitting genetic information.
  • The unique double-helix structure of DNA, with its complementary base pairing (adenine-thymine and cytosine-guanine), allows for the efficient storage and replication of genetic information. This structure ensures the stability and integrity of the genetic code, enabling the accurate transmission of hereditary traits from one generation to the next. The sequence of the four DNA bases encodes the genetic instructions that determine an organism's characteristics and guide its development and function.
• Describe the role of DNA in the regulation of gene expression and cellular function.
  • DNA plays a crucial role in the regulation of gene expression, which is the process of converting the genetic information encoded in DNA into the functional molecules (such as proteins) that carry out the various processes within a cell. The sequence and organization of DNA determine which genes are expressed, when they are expressed, and to what extent. This regulation of gene expression is essential for the proper development, growth, and maintenance of an organism, as well as its ability to respond to changes in the environment or internal conditions.
• Analyze the potential consequences of mutations in the DNA sequence and their impact on an organism's traits and health.
  • Mutations in the DNA sequence can lead to changes in the genetic code, potentially causing alterations in an organism's traits or the development of diseases. These mutations can range from subtle changes in a single base pair to larger-scale alterations in the structure or number of chromosomes. Depending on the nature and location of the mutation, it can result in the production of dysfunctional or altered proteins, which can disrupt normal cellular processes and lead to the manifestation of genetic disorders, increased susceptibility to diseases, or even the development of cancer. Understanding the impact of DNA mutations is crucial for the diagnosis, treatment, and prevention of genetic-based health conditions.

Related terms

Nucleotide:

The basic structural unit of DNA, consisting of a nitrogenous base, a sugar (deoxyribose), and a phosphate group.

Double Helix:

The unique twisted ladder-like structure of DNA, formed by two complementary strands of nucleotides held together by hydrogen bonds.

Chromosome: The condensed structure in the nucleus of a cell that contains the DNA and associated proteins, carrying the genetic information.