Introduction aux Acides Nucléiques
10 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Associez chaque type de nucléotide avec sa définition correcte :

Dinucléotide = 2 résidus de nucléotides Trinucléotide = 4 résidus de nucléotides Décanucléotide = 10 résidus de nucléotides Oligonucléotide = Entre 10 et 50 nucléotides

Associez chaque type de polynucléotide à sa caractéristique :

ADN = Support de l'information génétique ARN = Prend le relais dans certains virus ADN mitochondrial = Présent dans les mitochondries ADN chloroplastique = Présent dans les chloroplastes

Associez chaque type de lien entre nucléotides avec sa description :

Liaison phosphodiester = Unit les résidus par des liaisons 3' - 5' Liaison hydrogène = Relie les bases azotées entre elles Liaison covalente = Forte liaison entre atomes Liaison ionique = Interaction entre ions opposés

Associez chaque type d'organisme à la localisation de son ADN :

<p>Eucaryotes = Principalement dans le noyau Bactéries = Dans une seule molécule d’ADN Virus = Peut être composé d'ARN Plantes = Contient ADN chloroplastique</p> Signup and view all the answers

Associez chaque définition de génome avec son contexte :

<p>Génome eucaryote = Comprend l'ADN dans le noyau Génome viral = Peut être composé d'ARN ou d'ADN Jeu haploïde = Correspond aux chromosomes chez les diploïdes ADN mitochondrial = N'est pas inclus dans le génome d'un eucaryote</p> Signup and view all the answers

Associez les bases azotées avec leur classe (purine ou pyrimidine) :

<p>Adénine = Purine Uracile = Pyrimidine Thymine = Pyrimidine Guanine = Purine</p> Signup and view all the answers

Associez les ribonucléosides avec leur ribonucléotide correspondant :

<p>Adénosine = AMP Guanosine = GMP Uridine = UMP Cytidine = CMP</p> Signup and view all the answers

Associez les ribonucléotides avec leur nombre de groupements phosphoryles :

<p>AMP = 1 ADP = 2 ATP = 3 GMP = 1</p> Signup and view all the answers

Associez les déchets azotés avec leur équivalent en ribonucléotide :

<p>Thymine = TMP Cytosine = CMP Adénine = AMP Uracile = UMP</p> Signup and view all the answers

Associez les préfixes des désoxyribonucléotides aux bases azotées correspondantes :

<p>Désoxyadénine = dAMP Désoxyguanine = dGMP Désoxythymine = dTMP Désoxycytosine = dCMP</p> Signup and view all the answers

Study Notes

Introduction to Nucleic Acids

  • In 1869, Friedrich Miescher discovered a substance in cell nuclei rich in nitrogen and phosphorus.
  • He called it "nuclein."
  • Later identified as deoxyribonucleic acid (DNA) in the 20th century.
  • Nucleic acids are linear polymers of nucleotides, namely DNA and RNA.

Types of Nucleic Acids

  • Two types of nucleic acids:
    • Deoxyribonucleic acid (DNA)
    • Ribonucleic acid (RNA)
  • Crucial biological molecules.
  • Their functions extend beyond storing genetic information.

Functions of Nucleic Acids

  • Chemical mediators
    • Nucleosides and nucleotides (e.g., AMP)
  • Energy sources
    • Nucleotides
  • Enzyme cofactors
    • Nucleotides and dinucleotides
  • Biological catalysts (e.g., ribozymes in ribosomes)
  • Heredity carriers
    • DNA
  • Heredity expression agents (e.g., RNA)

Nucleic Acid Monomers: Nucleosides and Nucleotides

  • Nucleic acid monomers are classified into nucleosides and nucleotides.
  • Nucleosides are formed by a nitrogenous base and a sugar (ribose or deoxyribose), linked by a β-N-glycosidic bond.
  • Nucleotides are nucleoside phosphates; they consist of a nitrogenous base, a sugar, and one to three phosphate groups.

Nucleic Acid Composition

  • Nitrogenous bases:
    • Purines (adenine, guanine)
    • Pyrimidines (cytosine, uracil, thymine)
  • Sugars:
    • Ribose (in RNA)
    • Deoxyribose (in DNA)
  • Phosphate groups: present only in nucleotides

Nomenclature of Ribonucleotides

  • The document provides a table listing the ribonucleosides, ribonucleosides monophosphates, diphosphates and triphosphates for each base.

Functions of Nucleosides, Nucleotides, Dinucleotides, and Derivatives

  • Nucleosides and nucleotides, in their free state, serve as coenzymes.
  • They also act as chemical mediators or energy sources.
  • Cyclic nucleotides, like cyclic AMP (cAMP), are intracellular messengers in signal transduction pathways.

DNA: The Genetic Material

  • DNA carries genetic information in all cells except certain viruses where RNA takes this role.
  • In eukaryotes, DNA resides predominantly in the nucleus but also in mitochondria and chloroplasts.
  • The entire set of genetic material is known as the genome.
  • Chromosomes are highly organized DNA structures that allow its efficient storage.

DNA Structure

  • DNA consists of two polynucleotide chains that spiral to form a double helix.
  • The bases pair in a specific way: adenine pairs with thymine, and guanine pairs with cytosine.
  • The two strands run antiparallel to each other.

DNA Denaturation and Renaturation

  • Denaturation is the separation of the two strands of DNA due to heat, pH changes, or chemical treatment.
  • Renaturation involves the re-formation of the double helix when such treatment is removed.
  • The temperature at which half of the DNA strands have separated is called the melting temperature, or Tm.

The Central Dogma of Molecular Biology

  • DNA replicates, transcribing into RNA, and then translating into proteins.
  • This is the fundamental process by which genetic information flows in cells.
  • In more simple terms: DNA → RNA → Protein

RNA

  • RNA is a single-stranded polymer of ribonucleotides.
  • It is involved in several cellular functions, including protein synthesis.
  • Types of RNA:
    • Ribosomal RNA (rRNA)
    • Transfer RNA (tRNA)
    • Messenger RNA (mRNA)

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

Description

Ce quiz aborde les bases des acides nucléiques, leur découverte par Friedrich Miescher et leur classification. Vous apprendrez l'importance de l'ADN et de l'ARN dans les fonctions biologiques et la transmission héréditaire.

More Like This

Biological Significance of Nucleic Acids
40 questions
Nucleic Acids - Structure and Function
41 questions

Nucleic Acids - Structure and Function

BelievablePraseodymium4425 avatar
BelievablePraseodymium4425
Use Quizgecko on...
Browser
Browser