3.4 - Monosaccharides in Carbohydrates

Questions and Answers

What are carbohydrates?

The class of molecules that range from small sugar molecules to large polysaccharides, such as the starch molecules in pasta and potatoes.

What are monosaccharides?

Simple sugars and the monomers of carbohydrates.

How can monosaccharides form more complex sugars and polysaccharides?

Through dehydration reactions.

Generally, monosaccharides have molecular formulas that are some multiple of what?

CH2O Signup and view all the answers

What are the two trademarks of sugar?

A number of hydroxyl groups (-OH) and a carbonyl group (>C=O). Signup and view all the answers

What is glucose and what is its chemical formula?

Glucose is a common monosaccharide with the chemical formula C6H12O6. Signup and view all the answers

What determines whether the monosaccharide is glucose or fructose?

The location of the carbonyl group. Signup and view all the answers

What is the similarity between glucose and fructose?

They are isomers that differ only in the arrangement of atoms. Signup and view all the answers

How many carbon atoms do monosaccharides have?

3-7 carbon atoms. Signup and view all the answers

What are the most common types of monosaccharides?

5-carbon sugars (pentoses) and 6-carbon sugars (hexoses). Signup and view all the answers

Why are monosaccharides, especially glucose, so important?

They are the main fuel molecules for cellular work and provide immediate energy to tissues. Signup and view all the answers

Study Notes

Carbohydrates

Class of biomolecules that includes small sugars and large polysaccharides.
Includes key examples like starches found in pasta and potatoes.

Monosaccharides

Known as simple sugars and serve as monomers for carbohydrates.
Can form complex sugars and polysaccharides through dehydration reactions.
Molecular formulas are typically multiples of CH2O.
Characterized by the presence of hydroxyl groups (-OH) and a carbonyl group (>C=O).

Glucose and Fructose

Glucose is a common monosaccharide with the chemical formula C6H12O6.
The position of the carbonyl group distinguishes glucose (an aldehyde sugar) from fructose (a ketone sugar).
Both are isomers, differing only in atomic arrangement, with fructose tasting sweeter than glucose.

Structure of Monosaccharides

Monosaccharides typically have 3 to 7 carbon atoms.
Most prevalent forms are 5-carbon sugars (pentoses) and 6-carbon sugars (hexoses).
In aqueous solutions, pentoses and hexoses commonly form ring structures.

Importance of Monosaccharides

Serve as main fuel molecules for cellular activities.
Cells derive energy from glucose breakdown.
Glucose can be administered in aqueous solutions for immediate energy, especially for sick or injured patients.
Monosaccharides act as raw materials for synthesizing other organic molecules, including amino acids and fatty acids.

Description

This quiz focuses on the simplest carbohydrates, monosaccharides, and their role in forming complex sugars and polysaccharides. It covers key definitions and characteristics of carbohydrates and monosaccharides. Test your knowledge on these essential biomolecules!