Bio 126- Macromolecules

Question 1

All macromolecules are

Answer 1

polymers – built up from smaller units (mers)

Question 2

Poly means

Answer 2

“many” thus poly–mer = many units

Question 3

In science we use the terms: 
	MONO = 
	BI/DI = 
	TRI = 
	POLY =

Answer 3

1
2
3
MANY

Question 4

In the case of carbohydrates, each unit (mer) is called a

Answer 4

saccharide

Question 5

a single sugar molecule would be called a

Answer 5

monosaccharide

Question 6

CARBOHYDRATES contain

Answer 6

C, H and O
CARBON WATER
The H and O are in the ratio 2:1 as in water (H2O)

Question 7

Carbohydrates are generally

Answer 7

SUGARS or STARCHES.

Question 8

Thus we have a simple sugar (monosaccharide) called

Answer 8

GLUCOSE = C6H12O6 or [6 X ( C1 : H2 : O1 )]

Question 9

Monosaccharides may exist as units with different

Answer 9

numbers of carbon atoms

Question 10

we can have Triose

Answer 10

(3C) sugars

Question 11

We can have Pentose

Answer 11

(5C) sugars

Question 12

We can have Hexose

Answer 12

(6C) sugars

Question 13

Notice that ALL sugars are given names ending in

Answer 13

– OSE e.g fructose, glucose, maltose, ribose.

Question 14

Depending where the C=O bond is in the sugar, Sugars may also exist as

Answer 14

ALDOSES (aldehydes)- C=O bond at the end of the chain

or

KETOSES (ketones)- C=O bond is in the middle of the chain

Question 15

The most common way to represent sugars is in their cyclic form but without showing the actual carbons at each corner – called an

Answer 15

abbreviated ring structure

Question 16

If we have TWO monosaccharide units joined together, by a glycosidic linkage,
the sugar is called a

Answer 16

DISACCHARIDE.

Examples: maltose, sucrose

Question 17

The formation of a disaccharide from two monosaccharides is a

Answer 17

DEHYDRATION reaction- since a water molecule is released as the two sugars are linked together.

Question 18

DEHYDRATION reaction

Answer 18

• since a water molecule is released as the two sugars are linked together.

Question 19

In a Dehydration Synthesis reaction, Since it usually involves synthesis of a larger molecule - it is often called a

Answer 19

a Dehydration Synthesis reaction

Question 20

to split a disaccharide into two monosaccharides -

Answer 20

a WATER molecule must be re-inserted between them.

Question 21

to split a disaccharide into two monosaccharides - a WATER molecule must be re-inserted between them.
This is called a

Answer 21

Hydrolysis reaction.

Question 22

When many sugar units are joined together - this is called a

Answer 22

Polysaccharide.

Question 23

Polysaccharide. 4 Examples:

Answer 23

Starch, Glycogen, Cellulose, Chitin

Question 24

There is a significant difference in the way different polysaccharides are built up.

Answer 24

The C1-C4 linkages are different in starch and cellulose.

Question 25

In starch - all the monosaccharides are the same way around - so that the dehydration linkages are "straight across." This is called a

Answer 25

1-4 α link.

Question 26

In cellulose - the monosaccharides are oppositely placed alternately - (i.e, every second one is upside down) Thus the dehydration linkages have to go at an angle (obliquely) between each sugar unit. This is called a

Answer 26

1-4 β link

Question 27

Human enzymes are unable to break the 1-4 ___link.

Answer 27

1-4 β link - which is why we cannot digest cellulose

Question 28

Human enzymes are able to break the 1-4 ___link.

Answer 28

1-4 α link - and so can easily break down starch - into its many sugar units.

Question 29

Sugars are stored in the human liver as another polysaccharide macromolecule -

Answer 29

Glycogen - again with 1-4 α links (but also 1-6 α links).

Question 30

Starch and Glycogen are examples of

Answer 30

storage polysaccharides - used to store energy.

Question 31

_____ is another polysaccharide - used by arthropods like insects to form the hard exoskeleton that surrounds and protects the soft innards.

Answer 31

Chitin (ky~tin)

Question 32

Chitin (ky~tin) also contains _____ in the molecule as an amine.

Answer 32

Nitrogen

Question 33

What is also used to make surgical thread that breaks down naturally in the body after the wound has healed.

Answer 33

Chitin (ky~tin)

Question 34

Cellulose and Chitin are examples of

Answer 34

structural polysaccharides - used to form rigid structures for protection.

Question 35

Chitin forms the _____ of insects

Answer 35

exoskeleton

Question 36

LIPIDS – also called FATS – all contain

Answer 36

C and H with O – but contain lots of Hydrogen

Question 37

Lipids are

Answer 37

HYDROPHOBIC – soluble in (mix with) oils/fats but not water

Question 38

Lipids are all made of TWO basic PARTS

Answer 38

``` 1. A FATTY ACID C – C – C – COO(H)   2. An ORGANIC ALCOHOL C – C - OH ```

Question 39

Just as in carbohydrates - the alcohol and fatty acid are linked together by

Answer 39

dehydration reactions - one water molecule being removed for each fatty acid that is linked to the alcohol

Question 40

In the case of triglycerides - a fat molecule is formed with THREE identical fatty acids linked to the glycerol. Once the water has been removed - the resulting bonds between alcohol and fatty acid - are called

Answer 40

ester linkages.

Question 41

In fats (the fatty acid part) the carbon atoms can be joined together in 2 different ways:

Answer 41

1. SINGLE BONDS (SATURATED)-Each carbon atom holds the MOST (2) hydrogens. 2. DOUBLE BONDS (UNSATURATED)-Carbon atom each side of double bond holds ONE hydrogen.

Question 42

If this "unsaturation" (double-bond) happens only once in the whole molecule - then the fat is said to be

Answer 42

Monounsaturated

Question 43

If this "unsaturation" (double-bond) happens more than once - the molecule is said to be

Answer 43

Polyunsaturated

Question 44

Lipids that are totally saturated are solid at room temperature and are called

Answer 44

FATS

Question 45

Lipids that are unsaturated - especially those that are polyunsaturated - are liquid at room temperature - and are called

Answer 45

OILS This is because saturated fats have "tails" that pack closely together and allow for a solid structure - whereas those with unsaturated molecules have kinked "tails" that do not pack closely together - and the result is a liquid.

Question 46

Straight tails cause the lipid's physical state to be

Answer 46

solid at room temperature

Question 47

Kinked tails cause the lipid to be

Answer 47

liquid (oil).

Question 48

A very special kind of lipid that has a structure with a “head’ and “tails.”

Answer 48

Phospholipids

Question 49

Phospholipids-The head contains phosphates and is

Answer 49

POLAR and HYDROPHILIC | -the head mixes with water

Question 50

Phospholipids- The tails are

Answer 50

NON-POLAR and HYDROPHOBIC | -tails mix with oil/fat

Question 51

phospholipid is said to be

Answer 51

amphiphatic

Question 52

Phospholipids play important roles in everyday life - since one part mixes with water and the other with oil/fat - they are used extensively in

Answer 52

emulsifiers, soaps and detergents

Question 53

In living creatures Phospholipids play a vital role as an integral part of every cell - in the form of the

Answer 53

plasma membrane (PM)

Question 54

plasma membrane (PM)

Answer 54

which is formed of a double layer of phospholipids - the heads pointing out and in - with the tails in the middle layer.

Question 55

Another group of molecules - the steroids - have a molecular multi-ring structure. Some are lipids (steroid alcohols) - called

Answer 55

sterols.

Question 56

An example of a sterol is

Answer 56

Cholesterol - an important lipid that is also part of the plasma membrane of every animal cell.

Question 57

A sterol is a

Answer 57

steroid alcohol (as in fatty steroids) but not all steroids are sterols!

Question 58

Other important examples of steroids - are

Answer 58

hormones - e.g the sex hormones estrogen and testosterone. (Note they are steroids NOT sterols)