Chapter 7- Polysaccharides and Glycoconjugates

Question 1

most carbs occur as polysaccharides, aka ____

Answer 1

glycans

Question 2

What is a homopolysaccharide?

Answer 2

contain only 1 kind of monosaccharide unit

Question 3

what is a heteropolysaccharide?

Answer 3

contain 2 or more monosaccharides

Question 4

2 types of polysaccharides

Answer 4

1. storage polysaccharides
2. Structural polysaccharides

Question 5

Types of storage polysaccharides

Answer 5

• starch
• glycogen

Question 6

Types of structural polysaccharides

Answer 6

• cellulose
• agarose
• glycosaminoglycans

Question 7

Starch is a mixture of ____ and ______

Answer 7

alpha amylose
amylopectin

Question 8

alpha amylose causes the starch chain to ____

Answer 8

turn

Question 9

starch forms a _______ stabilized by H-bonds

Answer 9

left-handed helix

Question 10

Glycogen is similar to ____

Answer 10

amylopectin

Question 11

Why is glucose not stored in its monomeric form?

Answer 11

1. high degree of branching
2. Insoluble glycogen contributes to osmolarity
3. glycogen decreases the concentration gradient

Question 12

Glucose’s high degree of branching causes ____

Answer 12

rapid release of monosaccharide units (multiple enzymes can work at many spots simultaneously)

Question 13

glucose’s insoluble glycogen causes contributes____

Answer 13

little to osmolarity which would cause cells to burst from water entry

Question 14

glucose’s glycogen decreasing the concentration gradient causes ____

Answer 14

glucose to uptake in cells

Question 15

Cellulose is a linear polymer of ____

Answer 15

D-glucose

Question 16

Cellulose possesses _______

Answer 16

Extended conformation

Question 17

Strength of cellulose comes from ____

Answer 17

extensive H-bonding

Question 18

Cellulose strands line up into sheets which leads to:

Answer 18

• Sheets stack on each other (added strength)
• inter-sheet H-bonding
• Hydrophobic molecule

Question 19

it is ____ to break down cellulose

Answer 19

hard

Question 20

Degradation of cellulose is ____ due to _____

Answer 20

very slow
tight packing and H bonding

Question 21

what is agar?

Answer 21

a complex mixture of sulfated heteropolysaccharides

Question 22

What is agarose?

Answer 22

polymer of disaccharide agarobiose

Question 23

When agarose and water is heated and cooled down:

Answer 23

it forms a double helix that traps water in the central cavity, causing the structures to form a 3D matrix/ Gel

Question 24

what are glycoconjugates?

Answer 24

sugars that are conjugated to proteins and lipids

Question 25

Functions of glycoconjugates

Answer 25

• contribute to cell type uniqueness
• regular cell-cel recognition and interaction
• label proteins for localization/destruction

Question 26

All bacterial cell walls possess a strong protective polysaccharide layer called ____

Answer 26

peptidoglycan

Question 27

Lipopolysaccharide coats the outer membrane of ____

Answer 27

Gram-negative bacteria

Question 28

The composition of Lipopolysaccharide determines _____

Answer 28

the antigenicity of the bacteria

Question 29

LPS antigen structures play a role in ____

Answer 29

cell recognition evasion of the host immune system

Question 30

Gram staining interacts with the ____

Answer 30

peptidoglycan

Question 31

What is gram staining used for?

Answer 31

used as a stain to distinguish bacteria based on their cell wall composition

Question 32

Gram-positive bacteria characteristics

Answer 32

• thick layer of peptidoglycan
• one membrane
• retains gram stain

Question 33

gram-negative bacteria characteristics

Answer 33

• thinner peptidoglycan (between membranes)
• two membranes
• does not retain gram stain