Biology Unit 4: Nucleic Acids Review

General Characteristics of Nucleic Acids

• Nucleic acids are macromolecules essential for life.
• Composed of long chains of nucleotides, each consisting of a sugar, phosphate group, and nitrogenous base.

Functions of Nucleic Acids

• Store and transmit genetic information.
• Direct the synthesis of proteins through processes like transcription and translation.

Composition of Nucleic Acids

• DNA is made of deoxyribonucleotides, featuring deoxyribose sugar.
• RNA is composed of ribonucleotides, containing ribose sugar.

Kinds of Nucleic Acids

• Primary types include DNA (deoxyribonucleic acid) and RNA (ribonucleic acid).
• DNA is primarily found in the nucleus, while RNA is found throughout the cell.

Properties of Nucleic Acids

• Exhibit specific base pairing (A-T and C-G in DNA, A-U and C-G in RNA).
• Can form double-stranded structures (DNA) or single-stranded structures (RNA).

Derivatives of Nucleic Acids

• Include various forms such as cyclic AMP (cAMP) and nucleotide coenzymes like NAD+.
• Derivatives play roles in cellular signaling and metabolism.

Levels of Structure of Nucleic Acids

• Primary structure: sequence of nucleotides.
• Secondary structure: double helix in DNA; various structures in RNA including hairpins and loops.
• Tertiary and quaternary structures often refer to complex folding and interactions with proteins.

Bases of DNA

• Four nitrogenous bases: adenine (A), thymine (T), cytosine (C), guanine (G).
• A-T pairs form two hydrogen bonds, while C-G pairs form three hydrogen bonds.

Structure of DNA

• The double helix model was proposed by Watson and Crick.
• Antiparallel strands create a stable structure with the sugar-phosphate backbone on the outside and bases on the inside.

RNA Structure

• Generally single-stranded but can fold into complex three-dimensional shapes.
• Types of RNA include messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA), each serving distinct functions in protein synthesis.

Nucleoproteins

• Complexes of nucleic acids and proteins crucial for DNA packaging and regulation.
• Chromatin is a nucleoprotein that helps condense DNA in eukaryotic cells.

Nucleotides and Nucleosides

• Nucleotides consist of a nitrogenous base, a sugar, and one or more phosphate groups.
• Nucleosides are similar but do not contain phosphate groups; they consist only of a sugar and a nitrogenous base.

This quiz reviews the essential characteristics, functions, and properties of nucleic acids. Students will explore different types of nucleic acids, their structures, and related concepts such as nucleoproteins, nucleotides, and nucleosides. Perfect for consolidating knowledge in molecular biology.