biochem

Question 1

What are carbohydrates?

Answer 1

Organic hydrocarbon molecules made of Carbon, Hydrogen, and Oxygen

Question 2

What are some important functions of carbohydrates?

Answer 2

Source of energy
Store energy
form Structure of nucleic acids
form Structure of cell membranes

mnemonic: SSSS

Question 3

In what forms do carbohydrates store energy?

Answer 3

• Starch ( plants)
• Glycogen (animals / humans)

Question 4

What is the structure of nucleic acids in relation to carbohydrates?

Answer 4

• Deoxy-ribose in DNA
• Ribose in RNA

Question 5

How do carbohydrates contribute to cell membranes?

Answer 5

glycoproteins and glycolipids

Question 6

What is a monosaccharide?

Answer 6

The simplest form of carbohydrates
further classified by the number of carbons: trioses (3C), tetroses (4C), pentoses (5C), hexoses (6C)

Question 7

What are aldoses and ketoses?

Answer 7

Aldoses have an aldehyde group; ketoses have a ketone group

Question 8

Example of a pentose and aldose sugar?

Answer 8

Ribose

Question 9

Example of a hexose and aldose sugar?

Answer 9

• Glucose
• Galactose

Question 10

Example of a hexose and ketose sugar?

Answer 10

Fructose

Question 11

What are enantiomers?

Answer 11

Stereoisomers that are mirror images of each other

Question 12

Example of enantiomers?

Answer 12

• D-glucose * L-glucose

Question 13

What are epimers?

Answer 13

Stereoisomers that differ in the position of the hydroxyl group at one asymmetric carbon

Question 14

Example of C4 epimers?

Answer 14

D-glucose and D-galactose

Question 15

What are anomers?

Answer 15

Stereoisomers that differ in the position of hydroxyl groups at the anomeric carbon

Question 16

Example of anomer?

Answer 16

• Alpha glucose * Beta glucose

Question 17

What is a sugar alcohol?

Answer 17

A sugar derivative formed from excess glucose, e.g., Sorbitol

Question 18

What is a sugar acid?

Answer 18

A derivative of sugar involved in metabolic processes, e.g., Glucuronic acid

Question 19

What is a deoxy sugar?

Answer 19

A sugar with one oxygen of its hydroxyl group missing, e.g., 2-deoxy ribose

Question 20

What are disaccharides?

Answer 20

Carbohydrates formed by the joining of two monosaccharides

Question 21

What are glycosidic bonds?

Answer 21

The bonds that link monosaccharides to form disaccharides

Question 22

Example of a disaccharide found in milk?

Answer 22

Lactose (galactose + glucose)

Question 23

Example of a disaccharide found in tubers?

Answer 23

Sucrose (glucose + fructose)

Question 24

Example of a synthetic disaccharide used as a laxative?

Answer 24

Lactulose (galactose + fructose)

Question 25

What are reducing sugars?

Answer 25

Sugars that can react with Benedict's reagent or Fehling's solution

Question 26

Which sugars are considered reducing sugars?

Answer 26

All monosaccharides and all disaccharides except sucrose

Question 27

Example of a non-reducing sugar?

Answer 27

Sucrose

Question 28

What is glycogen?

Answer 28

A branched polysaccharide that serves as the main storage form of carbohydrates in animals

Question 29

Where is glycogen stored?

Answer 29

Liver and skeletal muscles

Question 30

What is starch?

Answer 30

A polysaccharide that is the main carbohydrate of the diet, available in plants

Question 31

What are the two components of starch?

Answer 31

* Amylose (linear) * Amylopectin (branched)

Question 32

How do humans digest starch?

Answer 32

By hydrolysis through the enzyme amylase

Question 33

What is cellulose?

Answer 33

A structural polysaccharide in plants that humans cannot digest

Question 34

How does cellulose affect digestion?

Answer 34

Prevents constipation by increasing intestine motility