Glycosidic bonds

Question 1

Monosaccharides are joined to

Answer 1

alcohols and amines through glycosidic linkages

Question 2

Sucrose

Answer 2

(Glucose + fructose)

(alpha-d-glucopyranosyl+beta-d-fructofuranose) alpha 1,2 glycosidic bond

Question 3

Lactose

Answer 3

(beta-d-Galactopyransoly+alpha-d-glucopyronosyl) beta 1,4 glycosidic bond

Question 4

Maltose

Answer 4

(alpha d glucopyranosyl)+(alpha d glucopyranosyl) combined via a beta 1, 4 glycosidic linkage

Question 5

alpha 1, 2 glycosidic bond =

Answer 5

sucrose

Question 6

beta 1,4 glycosidic bond =

Answer 6

lactose

Question 7

alpha 1, 4 glycosidic bond

Answer 7

maltose

Question 8

What’s wrong with drinking alcohol?

Answer 8

partial oxidation of ethanol produces acetylaldehyde, whose aldehyde groups are free to react with OH groups on proteins, glycosylating them and deforming them (marking them “nonself” to the immune system)

Question 9

homopolymers

Answer 9

a polysaccharide in which the repeating monosaccharides are identical (think homo = the same)

Question 10

glycogen

Answer 10

the most common homopolymer in animal cells, the storage form of glucose

large and branched

largely made up of alpha 1,4 linkages

Question 11

alpha 1,6 linkages

Answer 11

the “branching” glycosidic linkages in glycogen, present in 1/10 units

Question 12

the plant analog of glycogen and its forms

Answer 12

starch, amylose (unbranched starch) and amylopectin (branched starch)

Question 13

where is glycogen stored?

Answer 13

liver (to supply glucose between meals) and muscle to supply glucose during exercise

Question 14

Starch —-> stomach —->

Answer 14

amylose/amylopectin is broken down in duodenum, demonstrate the alpha 1,4 and alpha 1,6 breakdown of starch into their disaccharides

Question 15

Difference between glycogen and starch

Answer 15

1/10 branching in glycogen, 1/30 branching in amylopectin

Question 16

cellulose

Answer 16

glucose in beta 1,4 glycosidic linkage

Question 17

difference between glycogen and cellulose and starch

Answer 17

cellulose utilize beta 1,4 linkages, starch and glycogen both use alpha 1,4 linkages

Question 18

“fiber”

Answer 18

a polysaccharide we don’t digest, beta 1,4 linkage, cellulose

Question 19

If lactose and cellulose both share a beta 1,4 glycosidic linkage arrangement, why can’t we breakdown cellulose?

Answer 19

lactose is beta 1 d galactopyrnosyl + alpha 1 a d glucopyranose

in other words the corresponding enzyme (lactase) identifies beta 1,4 between a galactose and a glucose, while it can’t for the beta 1,4 between two glucose monomers

Question 20

Glycoproteins, classes and functions

Answer 20

Class 1: proteoglycans: structural integrity, cartilage, blood vessels, holds these things together! it’s the glue!

Class 2: glycoprotein: blood groups, hormones , erythropoietin (hormone secreted by kidney to stimulate blood production)

Glycolipids

Question 21

UDP

Answer 21

Uridine diphosphate: added to intermediates in glycolysis to make a bigger molecule (allows one of the carbons to build up a bigger “thing”)

Question 22

Mucins

Answer 22

mucos membranes possess them and secrete them (your spit!) proteins that have sugars on them, different from the other glycoproteins

Question 23

porphyrin ring’s importance

Answer 23

the “non recyclable” thing in blood recycling (iron is saved): during the chemically shredding of porphyrin ring, bilirubin is produced

Question 24

bilirubin

Answer 24

chemically identical to porphyrin ring, byproduct of porphyrin’s breakdown (swiss cheese like: planar and hydrophobic)

hydrophobic and planar; can’t be excreted normal via normal disposal means by itself, so sugar is added to make it more susceptible to water salvable

Question 25

Bilirubin diglucuronide

Answer 25

excreteable form of bilirubin

Question 26

N-linked oligosaccharides

Answer 26

sugars attached to an asparagine residue via 1,4 beta glycosidic linkages between glucose and N-acetylglucosamine All n linked oligosaccharides have common pentasaccharide core consisting of three mannose and two N-acetylglucosamine residues

Question 27

O-linked oligosaccharides

Answer 27

sugars attached to a serine or a threonine "reducing end" of the sugar is attached to a serine"

Question 28

How many branches are on a glycoproteins

Answer 28

20-40

Question 29

Mucins: structure, traits, explanation

Answer 29

Mucins consist of a polypetide backbone with n-acetylglucosamines o-linked to sialic acids, which interact with water to give mucous its characteristic wateryness wateryness allows them to adhere to epithelial tissues and and perform basic barrier defense

Question 30

Proteoglycans, names and their basic structure

Answer 30

Chondroitin 6 sulfate, keratan sulfate, heparin sulfate, dermatan sulfate, hyaluronate....repeating units in glycoaminoglycans and proteins

Question 31

N-linked oligosaccharides in glycoproteins all

Answer 31

contain an Asn (asparagine residue) plus three mannose sugars; uses Gln/GluNAc (N-linked acetrylglucosamines)

Question 32

O-linked oligosaccharides in glycproteins all

Answer 32

use an O linked Gln/GluNAc (N-linked acetylglucosamines), use threonine or Serine to link up with the peptide chain

Question 33

Glycoproteins, Proteoglycans, Mucin

Answer 33

``` glycoproteins = blood groups/hormones proteoglycans = structural role in connective tissues mucin= looks like a glycoprotein except it loves water and only uses sialic acid and Gln/GluNAc ```

Question 34

Name the proteoglycans

Answer 34

``` Chondroitin 6-sulfate keratan sulfate heparin dermantan hyaluronate ``` all suffixed with "sulfate"

Question 35

amphipathic

Answer 35

molecule with a hydrophilic head and a hydrophobic tail, spontaneously form sheaths

Question 36

micelle formation

Answer 36

occurs when soaps/detergents are used on a larger phospholipid bilayer, and the resulting "ionized" phospholipids (i.e. single fatty acid chains with a phosphorous head) conglomerate into "spherical" units > 20 nm in diameter.

Question 37

the miclelle versus the bilipid layer

Answer 37

the micelle is the least favored of the two possible conformations, the reason is that the two fatty acid chains on the phosophlipid cannot fit inside the micelle, so they will for the bilayer instead

Question 38

dimensions of the bilayer versus the micelle

Answer 38

>20 nm for the micelle, 1 mm for the lipid bilayer