CHM105: Chapter 15

What are carbohydrates primarily used for in the body?

Energy storage

What elements make up carbohydrates?

Carbon, hydrogen, oxygen

Carbohydrates are also known as:

Saccharides

How are carbohydrates produced in nature?

Photosynthesis in plants

The process in which carbohydrates are oxidized in living cells to produce energy is called:

Cellular respiration

What is the simplest type of carbohydrate?

Monosaccharide

A carbohydrate with two monosaccharide units is called a:

Disaccharide

What are polysaccharides composed of?

Many sugar units

Monosaccharides with an aldehyde group are classified as:

Aldoses

Monosaccharides with a ketone group are classified as:

Ketoses

A monosaccharide with six carbon atoms and a ketone group is called a:

Ketohexose

What is an example of an aldohexose?

Glucose

The sugar found in RNA is:

Ribose

A carbon atom bonded to four different atoms or groups is called:

Chiral

What are stereoisomers?

Isomers with the same bonding sequence but different spatial arrangements

Enantiomers are:

Isomers that are non-superimposable mirror images

The D and L designation of monosaccharides is based on:

The position of the —OH group on the highest-numbered carbon

In a Fischer projection, the most oxidized group is placed:

At the top

The Haworth structure of glucose forms a:

Six-membered ring

Which monosaccharide forms a five-membered ring in its Haworth structure?

Fructose

What is a reducing sugar?

A sugar that can be oxidized to form a carboxylic acid

Which reagent is used to test for reducing sugars?

Benedict’s solution

Which sugar is NOT a reducing sugar?

Sucrose

What is formed when a monosaccharide is reduced?

Sugar alcohol

What monosaccharides make up lactose?

Glucose + galactose

What type of glycosidic bond does maltose have?

α(1→4)

Which polysaccharide is used for energy storage in animals?

Glycogen

What polysaccharide is the major structural component of plant cell walls?

Cellulose

Why can humans digest starch but not cellulose?

Humans have enzymes to break α-glycosidic bonds but not β-glycosidic bonds

What is the difference between amylose and amylopectin?

Amylose is unbranched, while amylopectin is branched.