Oligosaccharides & Polysaccharides

Question 1

Define oligosaccharides.

Answer 1

A condensation product of 3-10 monosaccharides

Question 2

True or False:

Most oligosaccharides are not digested by human enzymes

Answer 2

True

Question 3

What is another name for raffinose? What is it?

Answer 3

Melitose

Trisaccharide

Question 4

Define polysaccharide

Answer 4

high molecular weight polymers

Question 5

Most carbs found in nature occur as

Answer 5

polysaccharides

Question 6

Polysaccharides are

Answer 6

large molecules of monosaccharides that are connected to each other through their anomeric carbons

Question 7

1. Polysaccharides are condensation products of _____

2. They can be ______ or _____

Answer 7

more than 10 monosaccharide units

linear or branched

Question 8

3 biologically important polysaccharides are:

Answer 8

starch, glycogen, and cellulose

Question 9

All 3 (biologically important polysaccharides) are ________ but they differ in the type of ______ ______ and/or the amount of ________

Answer 9

polymers of D-glucose
glycosidic bond
branching

Question 10

How do polysaccharides differ from each other?

Answer 10

• identity of their monosaccharide units
• length of their chains
• types of bonds linking the units
• degree of branching

Question 11

What are polysaccharides classified into?

Answer 11

homopolysaccharides

heteropolysaccharides

Question 12

Homopolysaccharides

Answer 12

when polysaccharides are composed of a single type of monosaccharide building block

Question 13

Heteropolysaccharides

Answer 13

polysaccharides composed of more than 1 type of monosaccharide

Question 14

Examples of Homopolysaccharides

Answer 14

starch
glycogen
cellulose
dextrins

Question 15

Heteropolysaccharides can be divided into

Answer 15

glycoseaminoglycans and mucilages

Question 16

Examples of glycoseaminoglycans

Answer 16

hyluronic acid
heparin
ABO blood

Question 17

Examples of Mucilages

Answer 17

• agar
• pectins
• hemicellulose

Question 18

Starches and dextrins ( polysaccharides)

Answer 18

• digested by human enzymes

- its hydrolysis provide glucose (the most important carb)

Question 19

Nonstarches (polysaccharides)

Answer 19

not digested by human enzymes and are the major component of dietary fiber

Question 20

What are the 2 types of polysaccharides?

Answer 20

storage polysaccharides

structural polysaccharides

Question 21

Storage and structural polysaccharides are made up of _______ _____, but they are _________ and ________ different

Answer 21

glucose units

structurally and functionally

Question 22

Storage polysaccharides

Name 3

Answer 22

contain only a-glucose units

3 important ones are starch, glycogen, and amylopectin

Question 23

Structural polysaccharides

Name 2

Answer 23

contain only B-glucose units

2 important ones are cellulose and chitin

Question 24

Chitin contains a

Answer 24

modified B-glucose unit

Question 25

Function of Starch

Answer 25

the main storage form of glucose in plant cells

Question 26

Structure of Starch

Answer 26

its structure is identical to glycogen except for a much lower degree of branching (ab every 20-30 residues)

Question 27

Pure starch is …………
Powder that is ………
Found in ………..
Gives blue color with ………..

Answer 27

white, tasteless, and odorless
insoluble in cold water
wheat, rice, corn, potatoes
iodine

Question 28

What is amylose?

Answer 28

a glucose polymer with a(1–>4) linkages

Question 29

What is amylopectin?

Answer 29

a glucose polymer with mainly a(1–>4) linkages, but it also has branches formed by a(1–>6)

Question 30

Function and Location of Glycogen

Answer 30

• a storage polysaccharide found in animals

- stored in the liver and muscles

Question 31

Structure of Glycogen

Answer 31

its structure is identical to amylopectin, except that a(1–>6) branching occurs about every 12 glucose units

Question 32

When glucose is needed, glycogen is

Answer 32

hydrolyzed in the liver to glucose

Question 33

Function of Cellulose

Answer 33

the main constituent of the plant’s cell wall

Question 34

Cellulose is

Answer 34

insoluble

Question 35

Structure of Cellulose

Answer 35

a polysaccharide consisting of a linear chain of several hundred to over 10 thousand B (1–>4) linked B-D-glucose units

Question 36

Why can some animals digest cellulose? Which animals?

Answer 36

some animals can digest cellulose with the help of bacteria in their stomachs
-ruminants and termites

Question 37

How do human digest cellulose?

Answer 37

we do NOT have the enzymes needed to digest the bonds in fibers

Question 38

What can cellulose be called?

What does it act as?

Answer 38

dietary fiber

acts as a hydrophilic bulking agent for feces

Question 39

What inulin?

Where is it found?

Answer 39

• It’s a polysaccharide of fructose

- its found in tubers and roots of some plants, readily soluble in water

Question 40

What can inulin be used for?

Answer 40

determining the glomerular filtration rate

Question 41

Can inulin be hydrolyzed by intestinal enzymes?

Answer 41

no

Question 42

What are the fructose units in inulin joined by?

Answer 42

a B (2–>1) glycosidic bond

Question 43

In general, plant inulin polymers contain between

Answer 43

20 and several thousand fructose units

Question 44

What is chitin?

What is composed of?

Answer 44

• is a structural polysaccharide found in the exoskeleton of insects
• composed of N-acetylglucoseamine units linked by B1–>4 bond

Question 45

What is dextrin?

Answer 45

the intermediate in the hydrolysis of starch