Nucleic Acids Chapter 1 Quiz

Mansoura National University

• Mansoura National University is a university in Egypt.
• The semester is 1.

Nucleic Acids

• Nucleic acids are intracellular components for storing and expressing genetic information
• Include DNA (deoxyribonucleic acid) and RNA (ribonucleic acid)
• Nucleic acids (DNA & RNA) are long chains of repeated nucleotides.

Learning Outcomes

• Identify nucleotides and nucleosides nomenclature and structure
• List functions of nucleotides and their biological importance.
• Recognize DNA structure
• Recognize RNA structure
• Recognize types of RNA
• Identify differences between DNA and RNA

Agenda

• Nucleotides and nucleosides (nomenclature and structure)
• Nucleotides of biological importance and their roles
• DNA (types and structure)
• RNA (types and structure)
• Structure/function relation of RNA
• Differences between DNA and RNA

Learning Outcome 1

• Identify nucleotides and nucleosides nomenclature and structure

Nucleotide Structure

• Nucleotides are the building blocks of DNA and RNA
• Each nucleotide has three parts: a nitrogenous base, a pentose sugar, and a phosphate group.
• Purines include adenine (A) and guanine (G).
• Pyrimidines include cytosine (C), thymine (T), and uracil (U).
• Ribose sugar is found in RNA.
• 2-deoxyribose sugar is found in DNA

Nucleoside

• Nucleosides are made of a nitrogenous base and a five-carbon carbohydrate (ribose).
• Nucleotides are nucleosides with an additional phosphate group.

Learning Outcome 2

• Functions of nucleotides and their biological roles

Functions of Nucleotides

• Building blocks of RNA and DNA.
• Source of energy (ATP, GTP).
• Mediating hormone action (cAMP, cGMP).
• Co-enzymes (NAD, FAD, Coenzyme A).
• Activation of chemical compounds (UDP-glucose, CDP choline, CDP-ethanolamine, PAPS, SAM).

Learning Outcome 3

• Recognize DNA structure

DNA Structure

• DNA is 2 strands of polynucleotides (d.AMP, d.GMP, d.TMP, d.CMP)
• The nucleotides are linked by 3', 5' phosphodiester bonds
• One strand of DNA has many millions of nucleotides
• DNA is a double helix, with paired strands and antiparallel orientation (one strand runs 5' to 3', the other runs 3' to 5').
• Base pairing rule (Chargaff's Rule): A pairs with T, and G pairs with C.
• DNA has a sugar phosphate backbone, within that the nitrogenous bases form hydrogen bonds.

Functions of DNA

• DNA stores and transfers genetic information and it is responsible for genetic information.
• DNA carries genetic information and is stored in the nucleotide sequence.
• DNA replicates in cell division.
• DNA directs synthesis of RNA (transcription).

The strands separate during replication

• The DNA strands separate during replication.

Structural forms of the double strand helix

• A-DNA
• B-DNA
• Z-DNA

Learning Outcome 4

• Recognize RNA structure

RNA Structure

• RNA (Ribonucleic acid) is single-stranded polynucleotides
• RNA contains four types of nucleotides: AMP, GMP, CMP, and UMP.
• The nucleotides are linked together by 3',5' phosphodiester bonds.
• RNA molecules are formed in the nucleus by transcription from DNA.

Learning Outcome 5

• Recognize types of RNA

Types of RNA

• Messenger RNA (mRNA): 5% of cellular RNA; carries messages from DNA to ribosomes for protein synthesis.
• Transfer RNA (tRNA): 15% of cellular RNA; brings amino acids to the ribosome during protein synthesis.
• Ribosomal RNA (rRNA): 80% of cellular RNA; a component of ribosomes, where protein synthesis takes place.
• Small nuclear RNA (snRNA): less than 1% of cellular RNA; involved in RNA processing.

Learning Outcome 6

• Recognize differences between DNA and RNA

Differences between DNA and RNA