Lecture 5: Introduction to Carbohydrates

Question 1

What is the role of carbohydrates? What is the C:H:O ration

Answer 1

-Energy production, recognition and signaling
-1:2:1

Question 2

What are some examples of monosaccharides

Answer 2

glucose, glactose, fructose, ribose,

Question 3

What are some examples of dissachrides

Answer 3

sucrose, maltose, lactose

Question 4

What are some examples of polysaccharides

Answer 4

glycogen, cellulose, chitin, amylose, amylopectin

Question 5

Humans mainly produce _____________ type of sugars

Answer 5

D Sugars

*we can break down both L and D but D is preferred

Question 6

____________: compounds that have the same chemical formula but are different in some way

Answer 6

Isomers

Question 7

_________________ are mirror images

Answer 7

Enatomers

Question 8

How are L and D isomers different

Answer 8

L OH is on the left side D is on the right side

Question 9

In terms of polarized light activity what is the difference between L and D glucose?

Answer 9

D glucose polarizes the light to the Right

L glucose polarizes the light to the Left

Question 10

_______________ differ in only one of their chiral carbons

Answer 10

Epimers

Question 11

In human cells epimer pairs often can be interconcerted by an enzyme called ____________

Answer 11

epimerase

Question 12

What is often lost during a cyclization reaction?

Answer 12

Water is often lost

Question 13

What is the name of the bond between dissachrides and the enzyme involved in the formation of disaccharides

Answer 13

glycosidic bond

glycosyltransferases

Question 14

What two sugars make of sucrose and what bond is between them

Answer 14

Glucose and fructose

alpha (1,2) glycosidic bond

Question 15

What two sugars make up lactose and the bond between them

Answer 15

glactose and glucose
Beta (1,4) glycosidic bond

Question 16

What two sugars make up maltose and the bond between them

Answer 16

glucose and glucose

alpha (1,4)

Question 17

What is glucogen and what bonds are involved?

Answer 17

Highly branch polymer of glucose. Major storage form of glucose in animals

Alpha (1,4) and (1,6) glycosidic bonds

Question 18

What is starch?

Answer 18

-Amylose: unbranched, alpha (1,4) glycosidic linkages
-amylopectin: branched; alpha (1,4) and (1,6) glycosidic linkages

Question 19

What is Cellulose?

Answer 19

-Unbranched glucose polymer in plants Beta (1,4) glycosidic linkages. Humans can not digest

Question 20

What is a reducing sugar

Answer 20

if the OH group on the anomeric carbon of a cyclized sugar is not linked to another compound by a glycosidic bond, the ring can open

Question 21

What test can be used to identify reducing sugars in urine? What sugar is typically identified?

Answer 21

Benedict reagent test. Typically shows glucose by turning brick red.

Question 22

What is a glycoprotein?

Answer 22

The protein is shorter with fewer sugars

Question 23

What is a proteoglycan?

Answer 23

primarily made of core protein with a long chain of sugars