Nucleic Acid

1. Nucleotides

1.1. phosphate group

1.2. pentose sugar

1.3. nitrogenous base

1.3.1. Pyrimidines

1.3.1.1. cytosine

1.3.1.2. thymine

1.3.2. Purines

1.3.2.1. adenine

1.3.2.2. guanine

2. antiparallel strands

2.1. two strand are run on opposite direction

3. RNA

3.1. rRNA (ribosomal RNA)

3.2. mRNA (messenger RNA)

3.3. tRNA (transfer RNA)

4. DNA

4.1. store in Histone

4.2. coils undergo supercoil to save space

4.3. supercoil DNA called chromosome

4.4. preserve genetic information

5. DNA Replication

5.1. helicase split DNA into its component strands

5.2. polymerase is major enzyme bulid double helix DNA from the separated strands using free nucleotides

6. how does DNA code for an organism

6.1. transcription

6.2. translation

7. Protein synthesis

7.1. mRNA carries information encoded by codon

7.2. tRNA contains ribonucleotides triplet called anticodon

7.3. Anti codon base pair with codon

7.4. An amino acid will be added to the 3 tRNA with the help of an enzyme called amino-acylsynthetase

7.5. Translation begins with start codon AUG and ends with stop codon (UAA, UAG or UGA)

8. RNA transcription

8.1. DNA is transcribed into RNA (mRNA) by RNA polymerase

8.2. mRNA carries genetic information in the form of genetic code

8.2.1. Exons: coding region Introns: non-coding region

8.3. In cytoplasm, mRNA with the help of tRNA and rRNA will direct protein synthesis called translation

9. Genetic code

9.1. mRNA contains three letter code triplet called codon

9.1.1. AAA – lysine (Lys) AUG – methionine (Met)