Fibrous Proteins and Muscle Proteins Quiz
38 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

Which of the following statements about fibrous proteins is true?

  • They can be digested easily.
  • They are soluble in water.
  • They are not thermostable.
  • They possess mechanical strength. (correct)

    • Collagen constitutes about 30% of total protein in the human body.

    True

    What are the main types of muscle proteins mentioned?

    Tropomyosin and Myosin

    The hardness of keratin increases with the amount of ______ present in its structure.

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

    Match the types of keratin with their sources:

    <p>Keratin = Ectodermal Collagen = Mesenchymal Elastin = Mesenchymal Silk Fibroin = Silk-producing organisms</p> Signup and view all the answers

    What property of collagen is primarily responsible for the pulling power in tendons and ligaments?

    <p>Pulling power</p> Signup and view all the answers

    Elastin contains significant amounts of hydroxylysine.

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

    What vitamin deficiency can lead to a failure in the formation of Tropocollagen?

    <p>Vitamin C</p> Signup and view all the answers

    ____ is a symptom associated with Ehlers-Danlos syndromes.

    <p>Dislocated joints</p> Signup and view all the answers

    Match the disease with its associated collagen defect:

    <p>Scorbutus = Hydroxyproline deficiency Ehlers-Danlos Syndromes = Type III Collagen defect Osteogenesis imperfecta = Type I Collagen synthesis deficiency None = No collagen defect</p> Signup and view all the answers

    What is the primary function of myoglobin?

    <p>Store oxygen in muscles</p> Signup and view all the answers

    Human Serum Albumin constitutes nearly 50% of all plasma proteins.

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

    What is the significance of the heme group in hemoglobin?

    <p>It binds oxygen reversibly due to the ferrous iron atom.</p> Signup and view all the answers

    Globulins are generally _____ than albumins and less soluble in water.

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

    Match the protein type to its characteristic:

    <p>Albumins = Carries ions, hormones, and fatty acids Alpha globulins = Class of globulins Gamma globulins = Comprising immunoglobulins Myoglobin = Single polypeptide with one heme group</p> Signup and view all the answers

    Which type of hemoglobin is primarily associated with adults?

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

    Deoxyhemoglobin can bind to carbon dioxide and hydrogen.

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

    What are the two states of hemoglobin and their affinities for oxygen?

    <p>T State (low affinity), R State (high affinity)</p> Signup and view all the answers

    HbF is made up of ______ and ______ subunits.

    <p>α, γ</p> Signup and view all the answers

    Match the types of hemoglobin with their description:

    <p>Hb Gower 1 = Embryonic yolk sac hemoglobin HbF = Fetal hemoglobin HbA = Main adult hemoglobin HbA2 = Minor adult hemoglobin</p> Signup and view all the answers

    Which of the following cross-links are found in elastin?

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

    Elastin is formed from multiple genetic types.

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

    What structural feature differentiates collagen from elastin regarding their helices?

    <p>Collagen has a triple helix, while elastin has random coils.</p> Signup and view all the answers

    In silk fibroin, nearly half of the amino acids are __________.

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

    Match the following features with the correct protein: Collagen, Elastin, Silk Fibroin.

    <p>Single genetic type = Elastin Triple helix structure = Collagen High content of glycine = Silk Fibroin</p> Signup and view all the answers

    Which property is NOT associated with globular proteins?

    <p>Mostly fibrous proteins</p> Signup and view all the answers

    Hydroxylysine is present in elastin.

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

    Name two types of cross-links found in elastin.

    <p>Desmosine and lysine-norleucine.</p> Signup and view all the answers

    Silk fibroin has a ___________ sheet structure.

    <p>β-pleated</p> Signup and view all the answers

    Which modification is NOT present in elastin?

    <p>Carbohydrate modification</p> Signup and view all the answers

    What is the Bohr effect primarily associated with?

    <p>Decreased affinity of hemoglobin for oxygen due to pH changes</p> Signup and view all the answers

    The binding of 2,3-BPG to hemoglobin increases its affinity for oxygen.

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

    What is the primary role of carbonic anhydrase in the blood?

    <p>Catalyze the conversion of carbon dioxide and water into carbonic acid.</p> Signup and view all the answers

    The shift of the HbO2 dissociation curve to the right occurs in ______ pH conditions.

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

    Match the following terms with their definitions:

    <p>Bohr Effect = Decreased affinity of oxygen due to increased CO2 and acidity 2,3-BPG = Compound that facilitates oxygen release from hemoglobin Carbonic Anhydrase = Enzyme that converts CO2 and H2O into H2CO3 Chloride Shift = Movement of chloride ions into red blood cells during CO2 transport</p> Signup and view all the answers

    Why is 2,3-BPG important for transfused blood?

    <p>It is essential for facilitating oxygen release to tissues.</p> Signup and view all the answers

    Carbon monoxide is a beneficial gas released during respiration.

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

    What happens to oxygen release when blood is transfused without 2,3-BPG?

    <p>Oxygen cannot be effectively released to tissues.</p> Signup and view all the answers

    Study Notes

    Protein Classification and Function

    • Proteins are classified based on shape (structural) and composition.
    • Structural proteins have various shapes, including fibrous and globular.
    • Fibrous proteins are typically insoluble in water, strong, and provide structural support. Examples include keratin, collagen, and elastin.
    • Globular proteins have a complex, roughly spherical shape, and are usually soluble in water. They have diverse functions. Examples include hormones, enzymes, antibodies, and transport proteins (like hemoglobin and myoglobin).
    • Protein composition can be simple or conjugated. Simple proteins consist only of amino acids. Conjugated proteins contain additional components such as metals, lipids, or carbohydrates.

    Learning Objectives

    • Students will be able to classify proteins.
    • Students will understand the structural properties of fibrous proteins.
    • Students will compare and contrast the structures of keratin, collagen, and elastin.
    • Students will know the definition and structural properties of globular proteins.
    • Students will understand the structures and functions of myoglobin and its oxygen-binding properties.
    • Students will understand the structures and functions of hemoglobin and its oxygen-binding properties.

    Classification of Proteins

    • Structural (Shape): Determined by amino acid sequence. Fibrous proteins are elongated and provide strength (e.g., keratin in hair). Globular proteins are compact and often have diverse functions.
    • Composition: Simple proteins consist only of amino acids. Conjugated proteins contain other molecules (e.g., heme in hemoglobin).

    Fibrous Proteins

    • Scleroproteins: Insoluble in water, resistant to digestion, provide strength and structure. Examples include keratin (hair, nails), collagen (connective tissue), elastin (elastic fibers).

    Collagen

    • Accounts for ~30% of total body protein and is essential for connective tissues.
    • Has various types, with different structures and functions.
    • Physical properties (e.g., elasticity, strength) differ depending on the tissue location.
    • Crucial for skin, bones, tendons, and ligaments.
    • Essential for wound healing.

    Elastin

    • Provides elasticity and flexibility in tissues such as skin, blood vessels, and lungs.
    • Predominantly hydrophobic.
    • Rich in glycine, alanine, and lysine; contains small amounts of hydroxyproline but no hydroxylysine.

    Silk Fibroin

    • A fibrous protein found in silk.
    • A β-sheet structure composed of repeating amino acid sequences (mostly glycine and alanine).
    • Provides strength and flexibility to the silk fiber.

    Globular Proteins

    • Mostly conjugated, meaning they have additional components besides amino acids.
    • Examples include albumins and globulins.
    • Diverse functions including catalysis, transport, storage, gene regulation, immunity, etc.
    • They are usually soluble in water

    Albumins

    • Part of the larger protein family.
    • Abundant in blood, approximately 50% of plasma proteins.
    • Involved in transporting hormones, fatty acids.
    • Important for maintaining osmotic pressure (keeping blood in the blood vessels).

    Globulins

    • Larger than albumins.
    • Less soluble in water.
    • Important in various bodily functions, including blood clotting, immune responses, and transporting various molecules.

    Hemoglobin and Myoglobin

    • Function: Carry or store oxygen.
    • Structure: Contain heme groups. These groups have iron, which binds to oxygen.
    • Myoglobin: Single polypeptide chain, stores oxygen in muscle tissue.
    • Hemoglobin: Four polypeptide chains, transports oxygen in the blood.

    2,3-BPG and Hemoglobin

    • 2,3-BPG is a molecule that binds to hemoglobin, reducing its affinity for oxygen, and aids the release of oxygen in tissues.

    Carbon Monoxide and Hemoglobin

    • Carbon monoxide binds tightly to heme, preventing oxygen binding.
    • It displaces the oxygen, effectively blocking oxygen transport.

    Bohr Effect

    • The effect of pH on hemoglobin's oxygen binding capacity.
    • As pH decreases, hemoglobin's affinity for oxygen decreases, facilitating oxygen release in tissues.

    Studying That Suits You

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

    Quiz Team

    Related Documents

    Protein Classification and Function PDF

    Description

    Test your knowledge about fibrous proteins, including collagen and keratin, as well as muscle protein functions. This quiz covers key properties, types, and common diseases associated with protein deficiencies. Challenge yourself with questions on the roles of different proteins in the human body.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser