Biochm Chapter 4

Question 1

Alll sugars have a what group

Answer 1

C=O

Question 2

Simplest Aldose is

Answer 2

Glyceraldhyde

Question 3

Simplest ketose

Answer 3

Dihydroxyacetone

Question 4

What does D fructose look like , like what makes it different

Answer 4

KETONE GROUP, only one with it

Question 5

How does glucose look different than galactose and mannose

Answer 5

They’re OH are on different sides

Glucose : RLRR
Galactose: RLLR
Mannose: LLRR

Glucose is RLRR
Galactose different on 3rd
Mannose different on 1st

Question 6

Optical isomers meaning

Answer 6

Same chemical formula, different in how they spatially arrange

Question 7

What is the rule for calculating. The number of stereoisomers with common backbone ?

Answer 7

2^n

N is the number of chiral carbons in the molecule

Question 8

d lcuose and L glucose what are these to each other

Answer 8

Enantiomers

Question 9

How do you when it is D or L system for molecules, what are these steps

Answer 9

Look for the chiral carbons furthest from the carbonyl group

If the OH group is on right side it is D

If OH group is on left side , its L

Question 10

In monosaccharides, which group is the nucelophile and which group is carbonyl

Answer 10

Hydroxyl g

Question 11

Monosaccharides undergo what reactions to form cyclic hemiacetals and hemiketals

Answer 11

Intraolecular

Question 12

For example glucose, which 2 things connect to make the cyclic structure

Answer 12

The C=O carbon and the last OH on the backbone

Question 13

New chiral centre when glucose becomes cyclic is called what carbon

Answer 13

Anomer

Question 14

In Haworth projection, how do you know if its alpha or beta glucose

Answer 14

If the OH is facing down in the anomeric carbon and oppposite side or ring in carbon 5, that is alpha

If its on same side its beta

Question 15

Alpha d glucose and beta d glucose are what

Answer 15

Epimers

Question 16

Right side of Fischer projections face what up or down

Answer 16

Down

Question 17

Left side of Fischer projections face up or down

Answer 17

Up

Question 18

Mutarotation meaning

What it do

How it happens

How can we speed it up

Answer 18

Linear to cyclic form, constant back and forth

Can change from alpha to beta inter conversion

Happens spontaneously in water

Best to have acid and base is better

Question 19

Is alpha or beta preferred in cyclic structures of lets say glucose

Answer 19

Beta due to less steric strain

Question 20

Aldoses like glucose can be oxidized at the aldehyde group to make what

Answer 20

Aldonic acid

Question 21

Sugars that can be oxidized are called

Answer 21

Reducing agent

Question 22

Sugars that are reducing sugars test positive in what reagents (2)

Answer 22

Tolles
Benedicts `

Question 23

If you use Benedict’s solution with glucose

What does it actually use, like what’s in it

What’s the side product

Answer 23

Cu (OH)2

The after product is a red solid Cu2O

Question 24

How do ketoses also act as reducing sugars test positive

Answer 24

Through tatuomerizaation
Rearrangement of bonds in compound to become aldoses

And then they test positive

Question 25

Monosaccharides can be reduced or oxidizes

Answer 25

Both

Question 26

If aldehyde group of monosaccriades is reduced, what does it form

Answer 26

Alditol ( sugar alcohol ) Hydroxyl becomes H

Question 27

How does esterificaiton of glucose happen

Answer 27

Because they have hydroxyl groups, can react with carboxlyic acid desrivtives to form esters

Question 28

What does phosphorylation of glucose do to glucose molecule

Answer 28

Connects PO4 to it

Question 29

Difference between esterfication and glycoside formation

Answer 29

Esterifcation : hydroxyl groups reacts with carboxylic acid or carbolxyic acid derivative to make ester Glycoside formation is the reaction between alcohol and hemiacetal group on sugar to yield alkoxy group

Question 30

How does tollens reagent confirm to you that it is reduced

Answer 30

Silvery mirror produced

Question 31

Does it make sense for carbs to get oxidizes or reduced What is the purpose

Answer 31

Aerobic metabolism requires reduced forms of electron carriers for oxidative phosphorylation They are oxidized to become primary energy source

Question 32

When dissachrides are formed, what is lost

Answer 32

Water

Question 33

Sucrose is made of what two

Answer 33

Fructose and glucose

Question 34

What is lactose made of

Answer 34

Galactose and glucose

Question 35

Maltose is made of what 2

Answer 35

Glucose 2 of them

Question 36

For sucrose what bond is it really

Answer 36

Glucose alpha 1,2 fructose

Question 37

For lactose what bond is it

Answer 37

Galactose, beta 1,4 glucose

Question 38

For maltose what type of bond is it really

Answer 38

Glucose alpha 1,4 glucose

Question 39

If polysaccharide is made of same sugar or different sugar what they called

Answer 39

Homopolysaccharide Heteropolysaccharide

Question 40

What is main polysaccharides component

Answer 40

D glucose

Question 41

Cellulose if made of what bond in terms of sugars

Answer 41

Beta D Glucose units and connected by beta 1,4 glycosidic bonds

Question 42

Starch is made of what bonds in terms of sugar

Answer 42

Alpha D glucose with alpha 1,4 glycosidic bonds

Question 43

We digest starches with what amylase

Answer 43

Alpha and beta

Question 44

Two types of starches Do they have branches, if so what’s the type

Answer 44

Amylose : linear and unbranched Amylopectin: Branched with a 1,6 branches

Question 45

What is glycogen in terms of sugars

Answer 45

Animal storage of glucose , highly branches

Question 46

Beta amylase leaves what To make what

Answer 46

Amylose To yield maltose

Question 47

Alpha amylase cleaves what To make what (2)

Answer 47

Amylopectin To make glucose and maltose

Question 48

What does more branching in glycogen benefit it

Answer 48

More soluble Faster mobilization of glucose

Question 49

What cleaves glucose from non reducing ends of glycogen

Answer 49

Glycogen phosphorylase

Question 50

In glycogen, when it is cleaved, what is produced

Answer 50

Glucose 1 phosphate

Question 51

If glycogen and amylopectin are cleaved by the side branches, which one should have higher enzymatic activity Why

Answer 51

Glycogen Because more branching