Carbohydrates Quiz on Oligosaccharides and Polysaccharides
32 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 oligosaccharides is NOT true?

  • They produce gaseous products when broken down by intestinal bacteria in humans.
  • They are typically found in onions, cabbage, broccoli, and wheat.
  • They are typically sweet and taste good. (correct)
  • They are composed of a short chain of monosaccharides linked together.

    • Which of these is NOT a common type of polysaccharide?

  • Lactose (correct)
  • Chitin
  • Dextran
  • Starch

    • Which type of polysaccharide is responsible for the structural integrity of plants?

  • Glycogen
  • Starch
  • Chitin
  • Cellulose (correct)

    • Which of the following oligosaccharides is NOT related to a bitter taste?

    <p>Fructose (B)</p> Signup and view all the answers

    What is the main difference between homopolysaccharides and heteropolysaccharides?

    <p>Homopolysaccharides are composed of a single type of monosaccharide, while heteropolysaccharides are composed of multiple types. (B)</p> Signup and view all the answers

    Which of the following pairs correctly matches a polysaccharide with its function?

    <p>Starch - energy storage in plants (A)</p> Signup and view all the answers

    Which of the following is a characteristic of disaccharides?

    <p>They are composed of two monosaccharides linked by a glycosidic bond. (B)</p> Signup and view all the answers

    Which of the following statements correctly compares fructose and sucrose?

    <p>Fructose is sweeter than sucrose. (C)</p> Signup and view all the answers

    Which of the following statements about oligosaccharides is FALSE?

    <p>All oligosaccharides, except disaccharides, are less common in nature. (A)</p> Signup and view all the answers

    Which of the following is NOT a derived carbohydrate?

    <p>Polysaccharides (C)</p> Signup and view all the answers

    What is the structural feature that distinguishes aldehydes from ketones?

    <p>Aldehydes have a carbonyl group at the end of the carbon chain, while ketones have a carbonyl group within the chain. (B)</p> Signup and view all the answers

    Which of the following is a true statement about monosaccharides?

    <p>Monosaccharides are the building blocks of all carbohydrates. (C)</p> Signup and view all the answers

    Which of the following correctly describes the relationship between disaccharides and monosaccharides?

    <p>All of the above are true statements. (D)</p> Signup and view all the answers

    What type of bond is responsible for linking monosaccharide units together to form larger carbohydrate structures?

    <p>Glycosidic bonds (C)</p> Signup and view all the answers

    Which of the following carbohydrates is classified as a trisaccharide?

    <p>Raffinose (D)</p> Signup and view all the answers

    What is the primary function of glycogen in the human body?

    <p>Storing energy in the form of glucose units (A)</p> Signup and view all the answers

    What is the most abundant organic molecule found on Earth?

    <p>Cellulose (B)</p> Signup and view all the answers

    Which of the following statements correctly describes monosaccharides?

    <p>They contain either a polyhydroxy aldehyde or a polyhydroxy ketone unit. (A)</p> Signup and view all the answers

    In the context of carbohydrate classification, which characteristic applies specifically to disaccharides?

    <p>They are formed by the glycosidic linkage of two monosaccharides. (A)</p> Signup and view all the answers

    Which carbohydrate structure primarily serves as a supportive structural component in plants?

    <p>Cellulose (B)</p> Signup and view all the answers

    Which statement is true regarding the energy stored in carbohydrates?

    <p>Glucose, starch, and glycogen act as a storehouse of chemical energy. (A)</p> Signup and view all the answers

    What is the general chemical formula for carbohydrates represented by the formula CnH2nOn?

    <p>It represents a hydrate of carbon, showing a specific ratio of elements. (D)</p> Signup and view all the answers

    Which monosaccharide is specifically classified as a ketotriose?

    <p>Dihydroxyacetone (D)</p> Signup and view all the answers

    What is the primary physiological significance of D-(+)-mannose in the human body?

    <p>It can be converted to usable glucose. (D)</p> Signup and view all the answers

    Which statement correctly describes the classification of monosaccharides based on their stereochemistry?

    <p>D and L isomers are determined by the orientation of the –H and –OH groups. (B)</p> Signup and view all the answers

    Which of the following is classified as an aldohexose?

    <p>D-(+)-galactose (B)</p> Signup and view all the answers

    Which carbohydrate is the final form into which all carbohydrates are degraded in the body?

    <p>D-(+)-glucose (C)</p> Signup and view all the answers

    Which pentose sugar is important as a building block of RNA and DNA?

    <p>D-ribose (A)</p> Signup and view all the answers

    Which of the following describes the spatial arrangement of an aldotriose?

    <p>It has a terminal aldehyde group. (D)</p> Signup and view all the answers

    What defines a ketohexose among monosaccharides?

    <p>It is a six-carbon sugar with a ketone group. (C)</p> Signup and view all the answers

    Which of the following is NOT a ketopentose?

    <p>D-(+)-galactose (B)</p> Signup and view all the answers

    Which carbohydrate is known for being used in hospitals as an intravenous source of nourishment?

    <p>D-(+)-glucose (C)</p> Signup and view all the answers

    Study Notes

    Carbohydrates - Structure and Function

    • Carbohydrates are the most abundant class of bioorganic molecules on Earth, produced by photosynthesis in green plants.
    • They are also known as saccharides due to the sweet taste of many.
    • Carbohydrates store chemical energy (glucose, starch, glycogen)
    • One gram of digested carbohydrate yields approximately 4 kcal of energy.
    • Complex carbohydrates are beneficial for a diet.
    • Carbohydrates are supportive structural components in plants and some animals (e.g., cellulose, chitin).
    • Carbohydrates form part of the structural framework of DNA and RNA.
    • Carbohydrate markers on cell surfaces are crucial for cell-cell recognition.

    Classification of Carbohydrates

    • Carbohydrates have the general formula (C_n(H_2O)_n).
    • (n) varies from 3 to 8.
    • They are classified based on the number of carbon atoms (triose, tetrose, pentose, hexose, heptose, octose).
    • They can be further classified as aldoses (aldehyde group) or ketoses (ketone group)
    • Monosaccharides are simple sugars, containing a single polyhydroxy aldehyde or ketone unit that can't be broken down further through hydrolysis.
    • Disaccharides contain two monosaccharide units covalently bonded, crystallizing as water-soluble solids.
    • Disaccharides produce monosaccharides upon hydrolysis.
    • Oligosaccharides contain 3-10 monosaccharides units, and disaccharides are the common type.
    • Polysaccharides contain tens of thousands of monosaccharides units.
    • Homopolysaccharides are polymers of a single monosaccharide (e.g., glycogen, cellulose, starch).
    • Heteropolysaccharides contain multiple different monosaccharides types (e.g., hyaluronic acid, heparin, chondroitin sulfate).
    • Derived carbohydrates have gone through chemical reactions to form other products, such as sugar acids, sugar alcohols, deoxysugars, and sugar amines.

    Carbonyl Group

    • A carbonyl group is a chemically organic functional group, consisting of a carbon atom double-bonded to an oxygen atom.
    • The two simplest examples of these are aldehydes and ketones.
    • Aldehydes and ketones are usually attached to another carbon compound.

    Monosaccharides

    • These are simple sugars with the general formula (C_nH_{2n}O_n), where n can range from 3 to 8.
    • Different numbers of carbons determine trioses, tetroses, pentoses, hexoses, heptoses, and octoses.
    • An aldose has an aldehyde group, and a ketose has a ketone group.

    Biochemically Important Monosaccharides

    • Glucose, fructose, galactose, and ribose are crucial for various biological processes.
    • Glucose is the most abundant monosaccharide found in nature and is also a key component of blood sugar.
    • Fructose is the sweetest of common sugars, found in fruits and honey.
    • Galactose is a component of milk sugar.
    • Ribose is a part of RNA and DNA.
    • D-Mannose is found in certain bacteria, fungi, and plants.
    • D-glucose is used in hospitals as an intravenous source for nutrition.

    Cyclic Forms of Monosaccharides

    • Hemiacetals and hemiketals are formed from the reaction between aldehyde or ketone and alcohol.
    • Cyclic hemiacetals/hemiketals exist widely in nature and are five-or six-membered rings.
    • There is an a- and β-form for these.
    • Mutarotation is the interconversion between the cyclic forms, (α-and β) of sugars, accompanied by a change in specific rotation. Only sugars that form hemiacetals or hemiketals exhibit this property.

    Disaccharides

    • Two monosaccharides are linked by an acetal formation reaction to form a disaccharide.
    • The bond formed is called a glycosidic bond.
    • Common examples of disaccharides include maltose, lactose, and sucrose.
    • Maltose consists of two glucose units connected by an α(1 → 4) glycosidic linkage.
    • Lactose consists of β-galactose and β-glucose linked by a β(1 → 4) glycosidic bond.
    • Sucrose consists of an α-glucose and a β-fructose linked by an α(1 → 2) glycosidic linkage.

    Oligosaccharides

    • Oligosaccharides are carbohydrates containing between three and ten monosaccharides.
    • Common examples include raffinose and stachyose, found in beans.

    Polysaccharides

    • Polysaccharides are macromolecules comprised of many monosaccharides joined by glycosidic linkages.
    • Starch is a storage polysaccharide in plants, composed of amylose and amylopectin.
    • Glycogen is an animal storage polysaccharide.
    • Cellulose is a structural polysaccharide in plants, composed of linear chains of β-glucose units connected by β(1,4) glycosidic linkages.
    • Chitin is a structural polysaccharide found in the exoskeletons of insects, crabs, and other arthropods.

    Acidic Polysaccharides

    • These have acidic groups and important biological functions.
    • Hyaluronic acid is found in the vitreous humor, along joint fluid.
    • Chondroitin sulfate plays a crucial structural role in cartilage, bone, and the cornea.
    • Heparin is an anticoagulant, preventing blood clot formation.
    • Alginic acid has a variety of applications, especially in food products.

    Dietary Considerations

    • The glycemic index (GI) measures how quickly dietary carbohydrates are digested and affect blood glucose levels.
    • Low-GI foods are preferable for better blood sugar control.
    • Unavailable carbohydrates, known as dietary fiber, are not digested by human enzymes.
    • Fiber aids digestion and can ease bowel movements.
    • Insufficient fiber consumption can affect digestive health.

    Studying That Suits You

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

    Quiz Team

    Related Documents

    Carbohydrates Structure and Function PDF

    Description

    Test your knowledge on the properties and functions of carbohydrates, focusing on oligosaccharides and polysaccharides. This quiz covers various statements, definitions, and differentiations related to these important biomolecules. Challenge yourself to identify true and false statements while learning more about carbohydrate structures.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser