Ergastic Cell Contents and Metabolites
28 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

Which of the following statements about alkaloids is correct?

  • Alkaloids can be characterized by their reaction with specific reagents. (correct)
  • Alkaloids typically do not contain nitrogen.
  • Caffeine is detected with Mayer’s reagent.
  • All compounds containing nitrogen are alkaloids.

    • What color does Dragendorff’s reagent produce in the presence of alkaloids?

  • Blue
  • Green
  • Orange (correct)
  • Creamy white

    • Which alkaloid is known to increase peripheral blood supply?

  • Morphine
  • Caffeine
  • Quinine
  • Ephedrine (correct)

    • What is the primary function of tannins as polyphenolic compounds?

    <p>Precipitate proteins</p> Signup and view all the answers

    What distinguishes caffeine from most other alkaloids in a chemical test?

    <p>It does not form any precipitate with Mayer’s reagent.</p> Signup and view all the answers

    What color is observed when testing for condensed tannins using ferric chloride?

    <p>Dark greenish black</p> Signup and view all the answers

    Which statement correctly describes the primary pharmacological action of tannins?

    <p>They serve as astringents and help in managing diarrhea and bleeding.</p> Signup and view all the answers

    What is the predominant characteristic of essential oils?

    <p>They consist of complex mixtures with a few major components.</p> Signup and view all the answers

    Which components are primarily responsible for the characteristics of essential oils, such as those from Mentha piperita?

    <p>Terpenes and alcohols</p> Signup and view all the answers

    What is the color change observed when essential oils are tested with Sudan III?

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

    What distinguishes primary metabolites from secondary metabolites in plants?

    <p>Primary metabolites are directly involved in normal growth.</p> Signup and view all the answers

    What is a common characteristic of secondary metabolites?

    <p>They often serve protective functions.</p> Signup and view all the answers

    Which of the following is categorized as a primary metabolite?

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

    Which statement about alkaloids is correct?

    <p>They contain a Nitrogen atom.</p> Signup and view all the answers

    Which of the following metabolites is NOT a primary metabolite?

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

    What is the role of primary metabolites in plants?

    <p>They are involved in growth and reproduction.</p> Signup and view all the answers

    What is an example of a secondary metabolite?

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

    Which of the following statements about primary metabolites is false?

    <p>Their absence leads to immediate death of the organism.</p> Signup and view all the answers

    Which pharmacological action is associated with thyme oil?

    <p>Antiseptic and antimicrobial</p> Signup and view all the answers

    What type of structures secrete volatile oils?

    <p>Secretory cells</p> Signup and view all the answers

    Which of the following oils is classified as an analgesic?

    <p>Clove oil</p> Signup and view all the answers

    What is the primary metabolite type formed by volatile oils?

    <p>Volatile compounds</p> Signup and view all the answers

    Which part of glycosides is responsible for pharmacological activity?

    <p>Aglycone part</p> Signup and view all the answers

    What is a characteristic of flavonoid glycosides?

    <p>They are known as antioxidants</p> Signup and view all the answers

    Which glycoside subclass can release toxic hydrogen cyanide (HCN)?

    <p>Cyanogenic glycosides</p> Signup and view all the answers

    What type of glycosides includes cardiac glycosides?

    <p>Steroidal glycosides</p> Signup and view all the answers

    Which of the following structures is NOT a way through which volatile oils are secreted?

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

    What common test is associated with fixed and volatile oils?

    <p>Red color with sudan III</p> Signup and view all the answers

    Study Notes

    Ergastic Cell Contents

    • Non-living substances present within cells
    • Found in cytoplasm and vacuoles
    • Can be identified through microscopic examination and chemical/physical tests
    • Divided into primary and secondary metabolites

    Primary Metabolites

    • Essential for plant survival
    • Involved in growth, development and reproduction
    • Include carbohydrates, proteins, and lipids

    Secondary Metabolites

    • Not essential for plant survival
    • Have other functions, such as defense mechanisms
    • Include alkaloids, volatile oils, tannins, flavonoids, etc
    • Absence of secondary metabolites does not lead to immediate death

    Alkaloids

    • Compounds of biological origin with a nitrogen atom
    • Derived from amino acids
    • Often have pharmacological activity
    • Names typically end in "-ine" (e.g., caffeine)
    • Often have a bitter taste
    • Examples include: Morphine, Quinine, Vincamine, and Ephedrine

    Chemical Identification of Alkaloids

    • Mayer's reagent produces a creamy white precipitate with most alkaloids (except caffeine).
    • Dragendorff's reagent produces an orange color.

    Tannins

    • Polyphenols with the ability to precipitate proteins
    • Historically used for leather production by cross-linking proteins
    • Two main types: Hydrolyzable tannins and Condensed tannins

    Test for Hydrolyzable and Condensed Tannins

    • Plant water extract is used.
    • Ferric chloride is added.
    • Condensed tannins react to form a dark greenish-black color.
    • Hydrolyzable tannins react to form a dark bluish-black color.

    Pharmacological Actions of Tannins

    • Astringent action: Anti-diarrheals and haemostatics
    • Chelating action: Antidote in poisoning by heavy metals and alkaloids
    • Polyphenolic nature: Antioxidant and anticancer

    Volatile Oils

    • Also known as essential oils
    • Volatile aromatic complex mixtures of relatively low molecular weight compounds (terpenes)
    • May contain up to 60 components, but two or three major components generally dominate (20-70%)
    • They give red color with Sudan III
    • Major components determine biological properties
    • Examples include Mentha piperita essential oil (menthol and menthone)

    Pharmacological Actions of Volatile Oils

    • Antiseptic and antimicrobial: Thyme oil
    • Analgesic: Mentha oil, clove oil
    • Sedative: Lavander oil
    • Spasmolytic: Anise oil
    • Fragrance: Lemon peel oil

    Secretory Structures

    • Volatile oils are secreted from:
      • Glandular hairs
      • Secretory cavities
      • Secretory ducts (vitta)
      • Secretory cells

    Fixed Oils vs Volatile Oils

    • Fixed oils are non-volatile, primary metabolites, and form triglycerides.
    • Volatile oils are volatile, secondary metabolites, and form terpenoids.
    • Both give a red color with Sudan III
    • Fixed oils leave a permanent spot on the paper while volatile oils do not.

    Glycosides

    • Biomolecules composed of two parts: a sugar part (glycone) and a non-sugar part (aglycone or genin).
    • The glycosidic bond links the two parts.
    • The aglycone part is responsible for the pharmacological activity.
    • Several types of glycosides exist based on the type of aglycone.

    Types of Glycosides

    • Steroidal glycosides (cardiac glycosides)
    • Phenolic glycosides
    • Cyanogenic glycosides
    • Thio-glycosides
    • Saponin glycosides

    Important Sub Classes of Glycosides

    • Flavonoid glycosides: Act as antioxidants.
    • Anthraquinone glycosides: Used as laxatives.

    Cyanogenic Glycosides

    • Contain a cyanogenic group (-CN)
    • Release hydrogen cyanide (HCN) gas upon hydrolysis, which is toxic.
    • The aglycone contains a sulfur atom.
    • Form a persistent froth when shaken (e.g., licorice).

    Studying That Suits You

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

    Quiz Team

    Related Documents

    Medicinal Plants Lecture 4 PDF

    Description

    Explore the fascinating world of ergastic cell contents, focusing on primary and secondary metabolites in plants. Understand the importance of these substances, including carbohydrates, proteins, alkaloids, and their identification methods. Test your knowledge on their functions and significance in plant biology.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser