Chapter 5 - Molecules of Life

Question 1

All biological macromolecules are made up of four classes namely:

Answer 1

1. Carbohydrates
2. Proteins
3. Nucleic acids
4. Lipids

Question 2

Describe the relation between polymers, monomers and macromolecules

Answer 2

Monomers are similar/identical molecules that are covalently bonded to make chains of polymer

Monomer + Monomer = Polymer

Question 3

How do monomers bond to create a polymer?

Answer 3

Through a dehydration reaction. When two molecules of monomers covanlently bond, they lose H2O.

Question 4

What is it called when H2O is added to the chain to break the polymer chain?

Answer 4

Hydrolysis

Question 5

Which three class of macromolecules are made up of polymers?

Answer 5

Nucleic acids, proteins and carbohydrates

Question 6

what are the monomers of carbohydrates called?

Answer 6

monosaccharides/simple sugars

Question 7

what is it called when a chain of monosaccharides bond together?

Answer 7

polysaccharides

Question 8

explain disaccharides

Answer 8

when two monosaccharides covalently bond with one another

Question 9

can different types of monomers exist in one class of macromolecules?

Answer 9

yes absolutely

Question 10

what’s the most common monosaccharide called?
1. fructose
2. sucrose
3. ketose
4. glucose

Answer 10

Glucose

(C6H12O6)

Question 11

how does the body recognize the different types of monosaccharides (simple sugars) in our bodies?

Answer 11

through the location of the carbonyl groups (whether they are ketose or aldehyde)
and through the numbers of carbon in the skeleton group

Question 12

What are the three main ingredients of a monosaccharide?

Answer 12

Hydrogen+ carbon + oxygens
COH

Question 13

What is the relationship between Aldose sugars and Ketose sugars?

Answer 13

They are two structural isomers that make up the two of the most fundamental monosaccaride groups

Question 14

What is the difference between Aldose sugars and Ketose sugars?

Answer 14

Aldose - placed at the end of the chain known as the aldehyde group
Ketose - placed in the middle of the chain known as the ketone group

Question 15

What are three carbon sugars called?

Answer 15

Trioses

Question 16

What are five carbon sugars called?

Answer 16

Pentoses

Question 17

Why are the five carbon sugars so important? (pentose)

Answer 17

Because one of the pentoses make up an important monosaccharide - ribosome which is the backbone component of RNA and DNA

Question 18

What are six carbon sugars called?

Answer 18

Hexose

Question 19

What are some common hexoses? do these hexoses consist of a different molecular formula?

Answer 19

Glucose
Fructose
Galactose

No, the monosaccharides pf same sugar groups do not contain different types of molecular formula, they are isomers

Question 20

are the monosaccharides forming a linear chain chemically?

Answer 20

Sugar groups containing more than 5 carbons (pentose) are all in ring forms due to the attraction between different groups

Question 21

What is the covalent bond between a carbohydrate molecule and another group called?
Does this covalent bond lose the H2O in the process?

Answer 21

A glycosidic bond,
yes

Question 22

Glucose + Glucose =

Answer 22

Maltose

Question 23

Sucrose = _____ + ______

Answer 23

Glucose + fructose

Question 24

What are the two main functions of polymers of sugars (polysaccharides)? Give a brief example

Answer 24

Storage and structure
storage - sugars such as starch containing energy for plants
structure - sugars are backbones of a cell wall in wood

Question 25

Starch and Glycogen serve what functions as a polysaccaharide?

Answer 25

Storage of energy

Question 26

What are storage polysacccharides of plants called? What sugar groups are they made of?

Answer 26

Starch - made entirely of glucose monomers

Question 27

What are animal and human storage polysaccharides called? Where is it stored?

Answer 27

Glycogen; in the liver/muscle cells

Question 28

How do storage polysaccharides give energy to plants/animals/humans?

Answer 28

Because glucose contains a lot of energy, breaking those bonds down releases the energy which the cell then uses

Question 29

How do you differentiate between starch and glycogen based on the chemical structure?

Answer 29

Starch is mostly linear in shape and structure unlike glycogen which branches out more in shape

Question 30

Name the structural polysaccharide of plants

Answer 30

Cellulose

Question 31

How are structural polysaccharides different from storage polysaccarides?

Answer 31

It is due to a difference of the placement of OH in the sugar rings. Storage polysaccharide's molecule >> -OH is placed on the bottom of the sugar ring and Structural polysaccaride's OH is placed on the top of the sugar ring | Storage - DOWN Structure - UP

Question 32

What is the difference between Beta and Alpha linkages?

Answer 32

When OH molecules placed on top of the sugar ring, they are called beta linkages. When OH molecules placed on bottom of the ring are called alpha linkages.

Question 33

What's the most prevalent polysaccharide on earth? Why?

Answer 33

Cellulose, because all plants have this structural polymer

Question 34

Why do different enzymes exist for the Alpha and Beta linkages occuring in polysaccharides?

Answer 34

Because an enzyme that breaks down Alpha linkages cannot break down Beta type of linkages and vice versa | So our body cannot digest wood or cellulose

Question 35

What is the structural polysaccharide of fungis/insects called? Where are they found?

Answer 35

Chitin, in the exoskeleton

Question 36

What is chitin made of?

Answer 36

N-acetylglucosamine

Question 37

Why do lipids not form polymers?

Answer 37

Because they contain hydrocarbons which make them very hydrophobic and avoid covalent bonding

Question 38

What are the three major subclasses of lipids?

Answer 38

Stereoids, fats and phospholipids

Question 39

Describe the structure of a Fat (Triacylglycerol) How do they bond?

Answer 39

three **fatty acids **(hydrocarbons) are joint to a **glycerol** chain acting as a backbone They bond through a dehydration reaction where glycerol and datty acids link together | Glycerol + fatty acids

Question 40

Which functional groups do fatty acids contain?

Answer 40

Carbonyl

Question 41

what are the two types of fatty acids called?

Answer 41

Saturated and Unsatured fatty acids

Question 42

Which type of fatty acid has no double bonding

Answer 42

Saturated

Question 43

Which fatty acid has the max number of hydrogen bonds?

Answer 43

Saturated

Question 44

Which fatty acids have one or more cis double bonds?

Answer 44

Unsaturated

Question 45

What are the main functions of Fat? Why?

Answer 45

Energy storage? because they are hydrocarbon rich meaning breaking those bonds releases a lot of energy

Question 46

Why are the structure of Saturated and Unsaturated fatty acids different?

Answer 46

Because Saturated fatty acids have no double bonds, they pack together tightly because unsaturated fatty acids have** one or more cis double bonds at the edge**, they form kinks and are more spaced out

Question 47

Which fatty acids cannot stay solid (are liquids) at room temperature?

Answer 47

Unsaturated

Question 48

Since butter is solid, is it saturated or unsaturated fatty acid?

Answer 48

Saturated

Question 49

Why can't our body digest trans fat?

Answer 49

Because the trans fat is a cis isomer of a fatty acid, our body's enzyme cannot recognize it and as a result, cannot digest it

Question 50

How is a trans fat created? Describe the process

Answer 50

It uses the chemical process of hydrogenation (it adds hydrogen to the unsatured fat creating a saturated fat)

Question 51

Describe the structure of a phospholipid

Answer 51

Two fatty acids + Glycerol (backbone) + Phosphate group (head of group)

Question 52

Explain the concept of a self assembly in forming chemical molecules? Give an example

Answer 52

When there's no need for an enzyme molecules to bond together - the creation of the phospholipd bilayer

Question 53

Structure of a stereoid

Answer 53

Lipids characterized by a carbon skeleton of four fused rings

Question 54

What are some subtypes of stereoids?

Answer 54

Testosterone, estrogen, cholestrol

Question 55

Amino acid that is most hydrophobic

Answer 55

Alanine

Question 56

How many amino acids are there

Answer 56

5