Nucleotides Composition and Structure
59 Questions
1 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

What are the two families of nitrogenous bases?

  • Cytosine and thymine
  • Deoxyribose and ribose
  • Adenine and guanine
  • Pyrimidines and purines (correct)

    • Which type of sugar is found in DNA nucleotides?

  • Ribose
  • Deoxyribose (correct)
  • Lactose
  • Glucose

    • What type of bonds join adjacent nucleotides in a polynucleotide?

  • Ionic bonds
  • Phosphodiester linkages (correct)
  • Covalent bonds
  • Hydrogen bonds

    • What is the name given to nitrogenous bases that can bond together due to their shapes?

    <p>Complementary bases</p> Signup and view all the answers

    In a DNA molecule, how do the two polynucleotides run in relation to each other?

    <p>Antiparallel</p> Signup and view all the answers

    Why is DNA used for long-term information storage in cells instead of RNA?

    <p>DNA is more stable and less prone to degradation</p> Signup and view all the answers

    How many covalent bonds can carbon form?

    <p>4</p> Signup and view all the answers

    Which atoms are involved in forming covalent bonds in organic molecules?

    <p>Carbon, hydrogen, nitrogen</p> Signup and view all the answers

    What gives organic molecules different chemical properties?

    <p>Functional groups</p> Signup and view all the answers

    How are macromolecules formed from monomers?

    <p>Condensation reactions</p> Signup and view all the answers

    What is the general term for the building blocks of proteins?

    <p>Amino acids</p> Signup and view all the answers

    What is the term for the long molecules formed by many amino acids linked together?

    <p>Polypeptides</p> Signup and view all the answers

    What is a structural difference between DNA and RNA?

    <p>In DNA, the nitrogenous base thymine is replaced by uracil in RNA.</p> Signup and view all the answers

    Which pentose sugar is found in DNA?

    <p>Deoxyribose</p> Signup and view all the answers

    What are the major functions of carbohydrates?

    <p>Fuel, building material, and cell identity markers</p> Signup and view all the answers

    What type of bond is formed between two monosaccharides during polymerization?

    <p>Glycosidic bond</p> Signup and view all the answers

    Which nitrogenous base is unique to RNA and not found in DNA?

    <p>Uracil</p> Signup and view all the answers

    What is the general term for the monomers of carbohydrates?

    <p>Monosaccharides</p> Signup and view all the answers

    Which type of polysaccharide is primarily used by animals for energy storage?

    <p>Glycogen</p> Signup and view all the answers

    What is the function of cellulose in plant cell walls?

    <p>Structural support</p> Signup and view all the answers

    Which class of large biological molecules do not form polymers?

    <p>Lipids</p> Signup and view all the answers

    What is the primary reason why lipids are hydrophobic?

    <p>Consist mostly of carbon-hydrogen bonds</p> Signup and view all the answers

    Which lipid is important for cell membranes due to its amphipathic nature?

    <p>Phospholipids</p> Signup and view all the answers

    What do lipids primarily function as in biological systems?

    <p>Energy storage</p> Signup and view all the answers

    How is the primary structure of a protein determined?

    <p>By the unique sequence of amino acids in a protein</p> Signup and view all the answers

    What can radically alter protein function?

    <p>A single amino acid change</p> Signup and view all the answers

    What is responsible for forming a protein's secondary structure?

    <p>Hydrogen bonds between the carboxyl group and the amino group</p> Signup and view all the answers

    What contributes to the distinctive three-dimensional shape of a polypeptide?

    <p>Interactions between R-groups and the peptide backbone</p> Signup and view all the answers

    When does a protein acquire its unique three-dimensional shape?

    <p>At the primary structure level</p> Signup and view all the answers

    What results in quaternary structure in proteins?

    <p>Two or more polypeptide chains coming together</p> Signup and view all the answers

    Where does protein synthesis take place in a eukaryotic cell?

    <p>Cytosol</p> Signup and view all the answers

    Which component of the endomembrane system is mainly involved in the synthesis of lipids?

    <p>Endoplasmic reticulum</p> Signup and view all the answers

    What is the function of rough endoplasmic reticulum (ER) in protein synthesis?

    <p>It has ribosomes attached and is involved in protein synthesis</p> Signup and view all the answers

    Which region of the endoplasmic reticulum lacks ribosomes?

    <p>Smooth ER</p> Signup and view all the answers

    What is the main function of smooth endoplasmic reticulum (ER) in a eukaryotic cell?

    <p>Detoxification of chemicals</p> Signup and view all the answers

    Which organelle is responsible for modifying, packaging, and transporting lipids and proteins in a eukaryotic cell?

    <p>Golgi apparatus</p> Signup and view all the answers

    What is the primary function of microfilaments in cell division of animal cells?

    <p>Pulling the duplicated chromosomes to opposite ends of the dividing cell</p> Signup and view all the answers

    What structures are found in the centrosome of animal cells?

    <p>Pairs of centrioles</p> Signup and view all the answers

    What happens during cytokinesis in animal cells?

    <p>Cytoplasm is equally distributed into two daughter cells</p> Signup and view all the answers

    What is the role of centrioles in cell division?

    <p>Pulling duplicated chromosomes to opposite ends of the dividing cell</p> Signup and view all the answers

    Why is the exact function of centrioles in cell division unclear?

    <p>Even without centrosomes, cells can still divide</p> Signup and view all the answers

    What is the main function of the Golgi apparatus?

    <p>Modification, sorting, and packaging of macromolecules</p> Signup and view all the answers

    What would be the consequence if the lysosomal membrane breaks down?

    <p>Release of inactive hydrolytic enzymes at neutral pH</p> Signup and view all the answers

    At what pH are the hydrolytic enzymes within lysosomes active?

    <p>pH 5</p> Signup and view all the answers

    What is the primary function of lysosomes in a cell?

    <p>Digestion of macromolecules</p> Signup and view all the answers

    Which organelle in a eukaryotic cell is primarily responsible for packaging materials into transport vesicles?

    <p>Golgi apparatus</p> Signup and view all the answers

    What maintains the acidic internal pH of lysosomes?

    <p>Proton pump in the lysosomal membrane</p> Signup and view all the answers

    Which molecules can cause oxidative stress in cells by reacting with and damaging DNA and lipid-based molecules?

    <p>ROSs</p> Signup and view all the answers

    Which component of the cytoskeleton is responsible for anchoring the nucleus and certain organelles in a cell?

    <p>Intermediate filaments</p> Signup and view all the answers

    What is the function of microfilaments within a cell?

    <p>Cytoplasmic streaming</p> Signup and view all the answers

    Which components control the beating of cilia and flagella in cells?

    <p>Microtubules</p> Signup and view all the answers

    What is the primary role of catalases and peroxidases within cells?

    <p>Breaking down ROSs</p> Signup and view all the answers

    In what cellular activity are microtubules, microfilaments, and intermediate filaments all involved?

    <p>Cell motility</p> Signup and view all the answers

    What distinguishes plant cells from animal cells in terms of their extracellular structure?

    <p>Plant cells have a cell wall while animal cells have an extracellular matrix (ECM)</p> Signup and view all the answers

    Which protein is the most abundant in the extracellular matrix (ECM) of most animal cells?

    <p>Collagen</p> Signup and view all the answers

    What are some key functions of the extracellular matrix (ECM) of animal cells?

    <p>Structural support, cell movement, and cell-to-cell signaling</p> Signup and view all the answers

    Which molecule is responsible for protecting the plant cell, maintaining its shape, and preventing excessive water uptake?

    <p>Cellulose fibers</p> Signup and view all the answers

    What do ECM proteins bind to in the plasma membrane of animal cells?

    <p>Integrins</p> Signup and view all the answers

    What type of carbohydrates are plant cell walls primarily made of?

    <p>Polysaccharides</p> Signup and view all the answers

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser