Genetics-And-Evolution-Molecular-Basis-Of-Inheritance-1

DNA Basics:

Structure: Double helix with two antiparallel strands.

Components: Deoxyribose sugar, phosphate group, nitrogenous bases (A, T, C, G).

Base Pairing: Adenine (A) pairs with Thymine (T), Cytosine (C) pairs with Guanine (G).

Functions of DNA:

Storage of Genetic Information: Encodes instructions for organism’s development and functioning.

Replication: Accurate copying of genetic information for cell division.

Transcription and Translation: DNA serves as a template for RNA synthesis; RNA translates genetic code into proteins.

Gene Expression: Regulates which genes are active or inactive.

Watson and Crick Model:

Double-Stranded Helix: Two antiparallel strands with right-handed twist.

Complementary Base Pairing: A-T, C-G with hydrogen bonds.

Sugar-Phosphate Backbone: Forms the DNA double helix structure.

Significance:

Replication Mechanism: Explains how genetic information is accurately copied.

Genetic Code: Basis for encoding proteins.

Mutations and Heritability: Understand how changes in DNA can lead to variations and hereditary traits.

DNA vs. RNA:

Sugar: DNA has deoxyribose; RNA has ribose.

Strands: DNA is double-stranded; RNA is usually single-stranded.

Bases: DNA uses Thymine (T); RNA uses Uracil (U) instead of T.

Function: DNA stores genetic info; RNA is involved in protein synthesis and various other cellular roles.

Location: DNA is primarily in the nucleus; RNA is found throughout the cell.

Stability: DNA is more stable; RNA is less stable due to 2’-OH group.