Carbohydrates Overview and Classification
23 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 is the blood group when neither GalNAc nor galactose is present?

  • A
  • O (correct)
  • B
  • AB

Humans can digest cellulose due to enzymes present in the mouth.

False (B)

What is the primary transport mechanism for glucose and galactose absorption in the intestine?

Sodium-dependent glucose cotransporter 1 (SGLT-1)

Blood glucose concentration is maintained at about _____ mM (_____ mg/dL).

<p>5, 90</p> Signup and view all the answers

Match the following transporters with the substances they transport:

<p>SGLT-1 = Glucose and Galactose GLUT-5 = Fructose GLUT-2 = From intestine to blood</p> Signup and view all the answers

What type of carbohydrate is known for its ability to bind large amounts of water and forms a gel-like matrix?

<p>Glycosaminoglycans (A)</p> Signup and view all the answers

Proteoglycans are protein-rich structures that contain long disaccharide units.

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

What is the role of glycoproteins in cellular functions?

<p>Glycoproteins are involved in cell-surface recognition, antigenicity, and serve as components of the extracellular matrix.</p> Signup and view all the answers

The primary structural difference between proteoglycans and glycoproteins is that glycoproteins are _____ rich.

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

Match the following components with their functions:

<p>Collagen = Provides structural support Elastin = Allows elasticity in tissues Fibronectin = Cell adhesion Glycans = Short oligosaccharides attached to proteins</p> Signup and view all the answers

In the context of blood group determination, if the terminal sugar on the glycan is galactose, which blood group is indicated?

<p>Blood group B (A)</p> Signup and view all the answers

Glycosylation is the least common posttranslational modification of proteins.

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

What structural components are associated with proteoglycans?

<p>Core proteins associated with glycosaminoglycans.</p> Signup and view all the answers

Which type of carbohydrate contains two monosaccharides?

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

All carbohydrates have the same general formula of (C.H2O)n.

<p>True (A)</p> Signup and view all the answers

What are the two main types of carbonyl groups found in monosaccharides?

<p>Aldehydes and ketones</p> Signup and view all the answers

The process of breaking down carbohydrates in the body is known as _______.

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

Match the following types of polysaccharides with their primary function:

<p>Glycogen = Storage Cellulose = Structural Starch = Storage Chitin = Structural</p> Signup and view all the answers

Which of the following is a six-carbon monosaccharide?

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

Chitin is a type of storage polysaccharide.

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

What is the suffix commonly used to indicate carbohydrates?

<p>-ose</p> Signup and view all the answers

Monosaccharides are classified based on the number of _______ atoms they contain.

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

Which of the following pairs produce a disaccharide through a glycosidic bond?

<p>Glucose + Glucose (A)</p> Signup and view all the answers

Flashcards

What are carbohydrates?

Carbonyl compounds with several hydroxyl groups. They are important energy sources and structural components in living organisms.

What is the general formula of carbohydrates?

A general chemical formula for carbohydrates.

Define isomers in the context of carbohydrates.

Molecules with the same chemical formula but different structures. For example, glucose and fructose have the same formula (C6H12O6) but different arrangements of atoms.

Classify carbohydrates based on the number of sugar units.

A classification of carbohydrates based on the number of sugar units they contain.

Signup and view all the flashcards

What are monosaccharides?

Simple sugars that cannot be broken down further.

Signup and view all the flashcards

What are aldoses?

A type of monosaccharide with an aldehyde group.

Signup and view all the flashcards

What are ketoses?

A type of monosaccharide with a ketone group.

Signup and view all the flashcards

What are disaccharides?

A type of carbohydrate consisting of two monosaccharides linked together by a glycosidic bond.

Signup and view all the flashcards

What are polysaccharides?

A type of carbohydrate consisting of many monosaccharides linked together.

Signup and view all the flashcards

Explain the digestion of carbohydrates.

The process of breaking down carbohydrates into simpler sugars for energy.

Signup and view all the flashcards

What is α-amylase?

The enzyme that breaks down α(1->4) glycosidic bonds in starch, releasing oligosaccharides and disaccharides.

Signup and view all the flashcards

What is a β glycosidic bond?

A type of glycosidic bond found in cellulose, which humans cannot digest.

Signup and view all the flashcards

What are intestinal disaccharidases?

A group of enzymes responsible for breaking down disaccharides into monosaccharides in the small intestine, allowing for their absorption.

Signup and view all the flashcards

What is SGLT-1?

A membrane protein found in the intestinal mucosal cells that transports glucose and galactose into the bloodstream with the help of sodium ions.

Signup and view all the flashcards

What is GLUT-5?

A transporter molecule found in the intestinal mucosal cells that facilitates the absorption of fructose.

Signup and view all the flashcards

Amylopectin: What makes it efficient?

A type of polysaccharide with branching structures, allowing for faster energy production.

Signup and view all the flashcards

Amylose: How is it structured?

A type of polysaccharide with a linear structure, providing a stable energy reserve.

Signup and view all the flashcards

Proteoglycan: What is it made of?

A large molecule composed of a core protein attached to long chains of negatively charged sugar molecules called Glycosaminoglycans (GAGs).

Signup and view all the flashcards

Glycosaminoglycans (GAGs): Describe their structure.

Long, unbranched chains of repeating disaccharide units that are negatively charged.

Signup and view all the flashcards

Glycoproteins: How are they different from proteoglycans?

Proteins with short, branched sugar chains attached to them. They are often involved in cell signaling and recognition.

Signup and view all the flashcards

Glycosylation: What is it and where does it occur?

The process of adding sugar chains to proteins after they are synthesized.

Signup and view all the flashcards

Extracellular Matrix (ECM): Describe its function.

The extracellular matrix (ECM) is a network of proteins and sugars that provides structural support and helps cells communicate with each other.

Signup and view all the flashcards

Glycoproteins: What are their key functions?

Proteins with sugar chains attached that play a role in cell recognition, antigenicity, and various extracellular functions.

Signup and view all the flashcards

Study Notes

Carbohydrates Overview

  • Carbohydrates are a group of carbonyl compounds (aldehydes or ketones) that also contain several hydroxyl groups.
  • The general formula for carbohydrates is (CH₂O)ₙ.
  • Isomers have the same chemical formula, but different structures. Fructose and glucose have the same formula (C₆H₁₂O₆).

Carbohydrate Objectives

  • Recognize the general structure of carbohydrates.
  • Classify carbohydrates.
  • Recognize disaccharides.
  • Recognize polysaccharides.
  • Explain carbohydrate-modified protein structures and their functions.
  • Explain carbohydrate digestion.

Carbohydrate Classification

  • Classification is based on the number of monomer units:
    • Monosaccharides (single unit)
    • Disaccharides (two units)
    • Oligosaccharides (few units)
    • Polysaccharides (many units)
  • The suffix "-ose" is added to the name of most carbohydrates.

Monosaccharides

  • Classified by:
    • Number of carbons (triose, tetrose, pentose, hexose, heptose, etc.)
    • Type of carbonyl group (aldose or ketose)
  • Examples:
    • Glucose, fructose, galactose, ribose.

Disaccharides

  • Formed by the combination of two monosaccharides via a glycosidic bond.
  • Examples:
    • Maltose (glucose + glucose)
    • Sucrose (glucose + fructose)
    • Lactose (galactose + glucose)

Polysaccharides

  • Formed by the combination of many monosaccharides via glycosidic bonds.
  • They are important for energy storage and structural support.
  • Examples:
    • Starch (energy storage in plants)
    • Glycogen (energy storage in animals)
    • Cellulose (structural component in plant cell walls)
    • Chitin (structural component in insect exoskeletons)

Protein-Carbohydrate Structures

  • Carbohydrates and proteins can combine to form glycoproteins and proteoglycans.
  • Glycoproteins have a protein core with attached carbohydrate chains.
  • Proteoglycans have a protein core with long, negatively charged carbohydrate chains (glycosaminoglycans) attached.

Digestion

  • Enzymes called glycosidases break down glycosidic bonds in carbohydrates during digestion.
  • Humans cannot digest cellulose because it has β-glycosidic bonds, which our enzymes cannot break down.
  • Alpha-amylase is instrumental in starch digestion in the mouth
  • Intestinal disaccharidases, and other enzymes break down disaccharides and other carbohydrates into monosaccharides for absorption.

Absorption

  • Monosaccharides are absorbed into the intestinal cells via active transport (some) and facilitated diffusion (some).
  • Important transport proteins for glucose and galactose are SGLT-1, while GLUT-2, 5 are for other transport methods.
  • These monosaccharides are then transported to the blood stream for use in the body.

Carbohydrate Metabolism

  • Blood glucose levels are tightly regulated.
  • Normal levels are about 5 mM (90 mg/dL).
  • Low levels lead to confusion and coma
  • High levels result in significant issues

Studying That Suits You

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

Quiz Team

Related Documents

Description

This quiz explores the fundamental concepts of carbohydrates, including their structure, classification, and functions. You'll learn about various types of carbohydrates such as monosaccharides, disaccharides, and polysaccharides, as well as their roles in biological processes. Test your knowledge on carbohydrate digestion and modified protein structures.

More Like This

Use Quizgecko on...
Browser
Open
Browser
Browser