Nucleic Acids and DNA Structure

Nucleic Acids

• Essential macromolecules for all life, comprising nitrogenous bases, deoxyribose sugar, and phosphate groups.

DNA

• Deoxyribonucleic acid; the genetic blueprint of organisms, encoding necessary instructions for growth and functioning.

Structure of DNA

• Exhibits a double helix formation resembling a twisted ladder, with a backbone made of deoxyribose sugars and phosphate groups.

Nucleotide

• Fundamental unit of DNA, consisting of a nitrogenous base, a sugar (deoxyribose), and a phosphate group.

Nitrogenous Bases

• Form the "rungs" of the DNA ladder; include Adenine (A) paired with Thymine (T), and Guanine (G) paired with Cytosine (C).

Hydrogen and Covalent Bonds

• Hydrogen bonds connect nitrogen bases together; covalent bonds link deoxyribose to phosphate groups within the DNA backbone.

Chromosomes

• Threadlike structures composed of chromatin DNA, responsible for carrying genes in a linear order, typically appearing as 'x' shapes.

Genes

• DNA sequences that code for proteins, determining specific traits in organisms.

DNA Replication

• The process of creating two identical DNA molecules from a single original strand, which is a semi-conservative method of inheritance.

Eukaryotic Cells

• Cells containing a membrane-bound nucleus and specialized organelles; examples include protists, fungi, plants, and animals.

Complementary Strands

• Each of the two chains that constitute a DNA double helix, whose bases correspond to each other.

Key Enzymes in DNA Replication

• Helicase: unwinds the double-stranded DNA.
• Ligase: connects complementary DNA strands post-replication by forming covalent bonds.

Base Pairs

• Specific pairs (A-T and G-C in DNA; A-U in RNA) that link the sugar-phosphate backbones of nucleic acids.

Types of Nitrogen Bases

• Purines: Include Adenine (A) and Guanine (G).
• Pyrimidines: Include Thymine (T), Cytosine (C), and Uracil (U).

Traits and Inheritance

• Traits are characteristics of organisms and are inherited through genes passed from parents.