Carbohydrate Types and Functions
34 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

What are monosaccharides primarily known for?

  • Being composed of two sugar units
  • Serving as a quick energy source (correct)
  • Being insoluble in water
  • Consisting of multiple sugar units

    • Which of the following is NOT considered a type of carbohydrate?

  • Disaccharides
  • Triglycerides (correct)
  • Oligosaccharides
  • Polysaccharides

    • What distinguishes polysaccharides from other types of carbohydrates?

  • They are typically sweet in taste
  • They are made up of only two sugar units
  • They are made up of more than two sugar units (correct)
  • They are a source of protein

    • Which carbohydrate is a complex carbohydrate primarily used for energy storage in animals?

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

    Which type of carbohydrate is digested quickly and provides quick energy?

    <p>Simple carbohydrates</p> Signup and view all the answers

    What is the primary characteristic of soluble fibre?

    <p>It dissolves in water and forms a gel.</p> Signup and view all the answers

    What distinguishes functional fibre from dietary fibre?

    <p>Functional fibre is isolated or extracted and added to foods.</p> Signup and view all the answers

    Which food is a source of insoluble fibre?

    <p>Skins of fruits and vegetables</p> Signup and view all the answers

    What is the role of soluble fibre in the digestive system?

    <p>It significantly decreases gastric emptying time.</p> Signup and view all the answers

    Which of the following correctly defines total fibre?

    <p>The sum of dietary fibre and functional fibre.</p> Signup and view all the answers

    Which of the following correctly defines oligosaccharides?

    <p>Complex carbohydrates made up of 3-10 monosaccharides</p> Signup and view all the answers

    What is the primary function of glycogen in humans?

    <p>Storage form of carbohydrates for energy</p> Signup and view all the answers

    Which statement about starch is false?

    <p>Amylopectin is made solely of linear glucose chains.</p> Signup and view all the answers

    What type of linkages are present in amylose?

    <p>alpha (1-4) links</p> Signup and view all the answers

    What major characteristic of glycogen allows it to release energy quickly?

    <p>Highly branched structure</p> Signup and view all the answers

    What differentiates soluble fiber from insoluble fiber?

    <p>Soluble fiber dissolves in water, while insoluble fiber does not.</p> Signup and view all the answers

    What is the range of chains in glycogen's structure?

    <p>10-18 glucose units</p> Signup and view all the answers

    Which of the following polysaccharides is known for being a significant energy source for the body?

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

    What is gluconeogenesis?

    <p>Production of glucose from a non-carbohydrate source</p> Signup and view all the answers

    What happens to body proteins when glycogen stores are depleted?

    <p>They are broken down to produce glucose</p> Signup and view all the answers

    How much carbohydrate is needed daily to support bodily functions?

    <p>100 g</p> Signup and view all the answers

    What is the 'protein sparing action' of carbohydrates?

    <p>Carbohydrates allow for protein to be used for its essential functions</p> Signup and view all the answers

    What leads to ketosis in the body?

    <p>Inefficient breakdown of fatty acids</p> Signup and view all the answers

    Which hormone is secreted by the pancreas in response to high blood glucose levels?

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

    What is the glycemic index?

    <p>A ranking of how a food affects the glycemic response</p> Signup and view all the answers

    What condition results from insufficient insulin production or decreased cell sensitivity to insulin?

    <p>Diabetes mellitus</p> Signup and view all the answers

    Which type of diet has been associated with an increased risk of heart disease?

    <p>High in sugars</p> Signup and view all the answers

    What is the effect of high fibre diets on bowel disorders?

    <p>They can relieve or prevent certain bowel disorders.</p> Signup and view all the answers

    What type of carbohydrates can lead to high serum triglyceride levels?

    <p>Monosaccharides, especially fructose</p> Signup and view all the answers

    What is a potential benefit of viscous fibres in the diet?

    <p>Protection against diabetes</p> Signup and view all the answers

    Which statement about dietary fibre and cancer risk is true?

    <p>High fibre intake is linked to lower colon cancer incidence.</p> Signup and view all the answers

    What is a primary characteristic of soluble fibre?

    <p>It binds to dietary cholesterol in the gut.</p> Signup and view all the answers

    What is the unclear influence of dietary fibre mentioned in studies?

    <p>On obesity</p> Signup and view all the answers

    What are short-chain fatty acids (SCFA) produced from?

    <p>Fermentation of certain fibres by gut bacteria</p> Signup and view all the answers

    Study Notes

    Carbohydrate Types

    • Complex carbohydrates are oligosaccharides (3-10 monosaccharides) and polysaccharides (> 10 monosaccharides)
    • They are straight or branched chains of monosaccharides joined by condensation reactions.
    • Examples: starch, glycogen.

    Starch

    • Amylose is a continuous single chain of glucose molecules joined by alpha (1-4) links.
    • Amylopectin is a branched chain of glucose molecules joined by alpha (1-4) links with branches connected by alpha (1-6) links.
    • Different types of amylose and amylopectin contribute to different characteristics (flavor, solubility, thickening power) in food science.
    • From a nutritional perspective, starches are all the same and broken down to glucose.

    Glycogen

    • The storage form of carbohydrates (energy) in humans and animals.
    • Highly branched chains of glucose (10-18 chains).
    • High branching allows glycogen to bind with water (limited water storage).
    • Fast hydrolysis allows for a quick energy supply.
    • The body stores glycogen for approximately 12-18 hours.

    Carbohydrate Structure - Simple and Complex

    • Monosaccharides are made up of 1 sugar unit (single sugars).
    • Disaccharides are made up of 2 sugar units (double sugars).
    • Polysaccharides are made up of more than 2 sugar units.
    • Simple carbohydrates provide a quick energy source and are digested quickly.
    • Complex carbohydrates are digested slowly and provide a sustained release of energy.

    Fibre

    • Total fibre is made up of dietary fibre and functional fibre.
    • Dietary fibre is edible, non-digestible and derived from plants.
    • Functional fibre is isolated, extracted, and added to food or pills for health benefits.
    • Fibre can be described by its solubility and digestibility:
      • Solubility: the extent to which a substance can be dissolved in water.
      • Digestibility: the extent to which a substance can be broken down in the digestive system.

    Types of Fibre

    • Soluble (Viscous) fibre:
      • Dissolves and swells in water, forming a gel.
      • Slows down digestion, delaying gastric emptying.
      • Helps to lower cholesterol levels.
    • Insoluble (non-viscous) fibre:
      • Does not dissolve in water.
      • Provides roughage and bulk, helping to keep you regular.
      • Helps to prevent constipation.

    Examples of Soluble and Insoluble Fibre

    • Soluble Fibre: Fruits (pectins), legumes, oats, flaxseed, barley, rye, guar gum, acacia gum, carrageenan, psyllium, some hemicelluloses.
    • Insoluble Fibre: Skins of fruits and vegetables, broccoli, celery, blackberries, raspberries, whole wheat pasta, brown rice, nuts and seeds.

    Gluconeogenesis

    • The body produces glucose from various 3C substrates including protein and pyruvate.
    • Gluconeogenesis is the process of making glucose from non-carbohydrate sources (gluco = glucose; neo = new; genesis = making).

    Problems with Insufficient Dietary Carbohydrate

    • Ketosis: inefficient breakdown of fatty acids.
    • Protein breakdown to produce glucose: occurs during starvation or insufficient dietary carbohydrate.
    • Adults need a minimum of 100 g/day of carbohydrates to supply sufficient glucose for bodily functions.

    Insufficient Glucose in the Body: Protein Breakdown

    • When there is insufficient carbohydrate, the body depletes muscle glycogen stores.
    • When glycogen stores are depleted, the body breaks down body protein to produce glucose.
    • This protein breakdown can lead to problems with growth, maintenance, nutrient transport, hormone production, and immune system regulation.

    The Protein-Sparing Action of Carbohydrates

    • Diets providing enough carbohydrate "spare" protein, meaning they preserve the body's use of protein for its intended and essential functions.

    Blood Glucose Regulation

    • Diabetes mellitus: disease caused by either insufficient insulin production or decreased sensitivity of cells to insulin, leading to elevated blood glucose levels.
    • Hypoglycemia: Low blood glucose levels, usually below 2.2 to 2.8 mmol/L.
    • Blood-glucose response curve: shows changes in blood glucose levels after consuming food.

    Hormones Involved in Blood Glucose Regulation

    • Insulin: secreted by the pancreas in response to a rise in blood glucose levels.
    • Glucagon: secreted by the pancreas in response to a decline in blood glucose levels.

    Glycemic Response and Glycemic Index

    • Glycemic response: How quickly and how high blood glucose rises after carbohydrates are consumed.
    • Glycemic index: ranks foods based on their impact on the glycemic response.

    Carbohydrates and Heart Disease

    • Diets high in sugar or refined carbohydrates raise blood lipid levels (triglycerides), increasing the risk of heart disease.
    • Diets high in whole grains can reduce the risk of heart disease.
    • High-carbohydrate diets can increase levels of triglycerides and high-density lipoproteins (HDL) cholesterol.
    • High serum triglycerides are higher when the primary carbohydrate in the diet is monosaccharides (simple sugars), especially fructose.
    • Soluble fibre can bind to dietary cholesterol in the gut and be excreted via waste.

    Indigestible Carbohydrates and Bowel Disorders

    • Diets high in fibre or indigestible carbohydrates can relieve or prevent certain bowel disorders: hemorrhoids, diverticulosis, diverticulitis, and constipation.
    • Epidemiological studies show lower incidence of colon cancer in populations with high-fibre diets.
    • More research is needed on the effects of fibre supplements and the relationship between fibre intake and certain cancers.

    Indigestible Carbohydrates and Other Conditions

    • Viscous fibre can increase insulin tissue response and protect against diabetes.
    • The influence of dietary fibre on obesity is unclear.
    • Some fibre is fermented by gut bacteria, producing short-chain fatty acids (SCFA) which cannot be absorbed.
    • Some fibre lowers blood cholesterol levels.

    Studying That Suits You

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

    Quiz Team

    Related Documents

    FNN100 Module 3: Carbohydrates (PDF)

    Description

    Explore the different types of carbohydrates, such as complex carbohydrates, starches, and glycogen. Understand their structures, functions, and roles in nutrition and food science. Test your knowledge on how these carbohydrates are composed and their significance in energy storage.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser