Structure and function of DNA

Full Answer Section

Function of DNA

DNA stores and transmits genetic information. The genetic information is encoded in the sequence of nucleotides. The sequence of nucleotides determines the order of amino acids in proteins. Proteins are essential for all life processes.

DNA is replicated during cell division. This ensures that each new cell has a complete copy of the genetic information.

DNA is also transcribed into RNA (ribonucleic acid). RNA is a single-stranded molecule that carries the genetic information from the DNA to the ribosomes, where proteins are synthesized.

How DNA stores and transmits genetic information

The genetic information in DNA is stored in the sequence of nucleotides. Each nucleotide triplet, or codon, codes for a specific amino acid. There are 20 different amino acids, and 64 different codons. This means that there are multiple codons that code for the same amino acid. This redundancy is important, as it makes the genetic code more resistant to mutations.

When a cell needs to produce a protein, the DNA is transcribed into RNA. The RNA is then translated into a protein at the ribosome. The ribosome reads the RNA codons one at a time and adds the corresponding amino acids to the growing protein chain.

The genetic information in DNA is transmitted from parents to offspring through sexual reproduction. When two gametes (sperm and egg) fuse, they combine their DNA to create a new individual. The new individual has a unique combination of the genetic information from its parents.

Mutations and genetic diversity

Mutations are changes in the DNA sequence. Mutations can occur spontaneously or be caused by environmental factors, such as radiation or chemicals.

Most mutations have no effect on the organism. However, some mutations can cause genetic diseases or disorders.

Mutations can also lead to genetic diversity. Genetic diversity is the variety of genetic information within a population. Genetic diversity is important for the survival of a population, as it allows the population to adapt to changes in the environment.

Conclusion

DNA is a complex and fascinating molecule that is essential for all life. It stores and transmits the genetic information that allows living organisms to grow, develop, and reproduce. DNA is also responsible for the diversity of life on Earth.

Sample Answer

Structure of DNA

DNA, or deoxyribonucleic acid, is a double-stranded molecule that contains the genetic instructions for all living organisms. It is made up of four different types of nucleotides: adenine (A), guanine (G), cytosine (C), and thymine (T). Each nucleotide is composed of a phosphate group, a sugar group, and a nitrogenous base.

The two strands of DNA are held together by hydrogen bonds between the nitrogenous bases. A pairs with T, and G pairs with C. This is known as complementary base pairing.