DNA
- STRUCTURE: DNA (deoxyribonucleic acid) is a molecule with a double helical structure, consisting of four bases (adenine, thymine, guanine and cytosine).
- Role: blueprint that stores genetic information and directs cellular activity.It is replicated in the cell and transmits genetic information from parent to child.
- The structure of DNA is shaped like a ‘double helix’.This resembles a twisted ladder: DNA is made up of four bases (adenine (A), thymine (T), guanine (G) and cytosine (C)), each of which forms a pair. A is linked to T and G to C. A is linked to T and G to C, respectively.These pairs correspond to the ‘rungs of the ladder’ of DNA.The structure of the double helix is important for keeping genetic information stable within the cell.
Gene
- Structure: the portion of a particular base sequence in DNA.
- Role: coding unit for a specific protein. Determines traits (e.g. eye colour, blood type).
Chromosome
- Structure: DNA tightly folded together with proteins. Human cells have 46 chromosomes.
- Role: distributes DNA appropriately during cell division.Contains a large number of genes in succession.
Summary
- DNA is the basic molecule containing all genetic information.
- Genes are specific parts of DNA that carry out specific functions.
- Chromosomes are condensed structures of DNA, which are clusters of genes.
Supervisor of the article
Dr. Hiroshi Oka
Graduated from Keio University, Faculty of Medicine
Doctor of Medicine
Medical Doctor
