Intro to Carbs
What Three elements are carbohydrates composed of?
Carbon (C), Hydrogen (H), and Oxygen (O).
What are simple sugars called?
Monosaccharides.
How many monosaccharides make up a disaccharide?
Two.
Polysaccharides are polymers of what specific monosaccharide?
D-glucose.
What are molecules called that have the same chemical formula but different structural formulas?
Isomers.
What is the empirical formula for carbohydrates?
(CH2O)n
A monosaccharide with six carbon atoms is classified as what?
A hexose.
What type of bond links two monosaccharides together to form a disaccharide?
A glycosidic bond.
Name two types of polysaccharides.
Homopolysaccharides and Heteropolysaccharides.
What type of isomers differ in configuration around only one specific carbon atom (not the carbonyl carbon)?
Epimers.
Besides carbohydrates, what is another common name for saccharides?
Sugars
What is the difference between an aldose sugar and a ketose sugar?
An aldose sugar has a carbonyl group that is an aldehyde, while a ketose sugar has a carbonyl group that is a ketone
What two monosaccharides combine to form maltose?
Two D-glucose molecules.
Which polysaccharide is a branched-chain polymer of α-D-glucose with α-1,4-glycosidic bonds and α-1,6 bonds for branches?
Amylopectin.
What are isomers that are non-superimposable mirror images of each other called?
Enantiomers
Name two functions of carbohydrates in living organisms.
Provide energy, act as a storage form of energy, structural components, cell-membrane components, cell-surface antigens, part of extracellular ground substance, associated with proteins and lipids, or part of RNA, DNA, and coenzymes
What is D-glucose commonly known as in the body?
Blood sugar.
Lactose, also known as milk sugar, is composed of which two monosaccharides?
β-D-galactose and α- or β-D-glucose.
What is the polysaccharide that stores α-D-glucose in muscle, and is similar to amylopectin but more highly branched?
Glycogen.
In a cyclic sugar structure, what is the term for the α or β configuration, determined by the position of the OH group on the anomeric carbon?
Anomers.
What process in plants produces carbohydrates like glucose?
Photosynthesis
Which monosaccharide is known as the sweetest carbohydrate and is found in fruit juices and honey?
D-fructose
What is table sugar called, and which two monosaccharides make it up?
Sucrose, composed of α-D-glucose and β-D-fructose.
Why can't humans digest cellulose?
Humans cannot break down the β-1,4-glycosidic bonds found in cellulose.
When glucose is placed in solution, its cyclic structures may open and close. Which form of glucose is present in the smallest amount at any given time in solution?
The open-chain form