Biological Role of DNA
1.synthesis of Protein –
- Transcription – The process in which the information present on a DNA molecule is written by a base sequence to its complementary sequence to mRNA.
- Translation – In this, the information located on the mRNA is translated as a chain of amino acids to form a protein.
2. DNA Replication –
- DNA Replication is the process in which two identical (Identical) copies are obtained from the original DNA.
- It is a biological process that takes place in all living beings and forms the basis of biological inheritance.
Rate – 1000 nucleotide /sec
3. DNA Inheritance
- DNA packs all the genetic information, and these are transferred from one generation to the next.
- Genes are made from DNA and chromosomes are made from genes. And this genetic information is transferred from one generation to another by chromosomes.
4. Mutation
- Abnormality comes in DNA due to change in base sequence of DNA.
- This abnormality becomes permanent in the gene and is passed on to the next generation, causing variations in the organisms.
- It can be produced artificially or naturally.
5. Genetic Code
- Genetic code is a 3-letter base sequence of nucleotide codons that codes for 20 types of amino acids and each triplet code has an amino acid code.
6. DNA Binding Protein
- It is a specific group of proteins bound to ssDNA.
- It protects DNA from forming intramolecular loops and breaks by nuclease and forms various types of structures.
- It helps in the expression of genes.
7. Genetic Recombination
- The exchange of genes takes place by crossing over the genes of two chromatids.
- In this, part of one chromatid connects with second chromatid and part of second chromatid with first chromatid.
- Genes are exchanged by this process, genetic variations arise in the daughter cell.
8. DNA Helicity
- The nucleotides in DNA are bound at a specific angle, due to which it is not linear but slightly bent along the length, and exhibits helicity.
9. DNA Looping –
- Protein is complexly bound to DNA, causing thousands (~10,000) of bases of DNA to come out as loops.
- This loop regulates many biochemical reactions.
Ex. – Lampbrush Chromosome