1.4: Starch, glycogen and cellulose

Question 1

Starch is a polysaccharide that is found in many parts of a plant in the form of small grains.

Especially large amounts occur where?

Answer 1

Especially large amounts of starch occur in:

1. Seeds
2. Storage organs

Question 2

Starch is a polysaccharide that is found in many parts of a plant in the form of small grains.

Especially large amounts occur in seeds and storage organs, such as what?

Answer 2

Especially large amounts of starch occur in:

1. Seeds
2. Storage organs, such as potato tubers

Question 3

Starch is a polysaccharide that is found in many parts of a plant in the form of small grains.

Especially large amounts occur in seeds and storage organs, such as potato tubers.

Starch forms an important component of food and is the major energy source in most diets.

Starch is made up of chains of a-glucose monosaccharides linked by glycosidic bonds that are formed by condensation reactions.

The chains may be what?

Answer 3

The chains of a-glucose monosaccharides linked by glycosidic bonds may be:

1. Branched

Or,

2. Unbranched

Question 4

Starch is a polysaccharide that is found in many parts of a plant in the form of small grains.

Especially large amounts occur in seeds and storage organs, such as potato tubers.

Starch forms an important component of food and is the major energy source in most diets.

Starch is made up of chains of a-glucose monosaccharides linked by glycosidic bonds that are formed by condensation reactions.

The chains may be branched or unbranched.

The unbranched chain is what?

Answer 4

The unbranched chain is wound into a tight coil that makes the molecule very compact

Question 5

The main role of starch is what?

Answer 5

The main role of starch is energy storage

Question 6

The main role of starch is energy storage, something its structure is what?

Answer 6

The main role of starch is energy storage, something its structure is especially suited for

Question 7

The main role of starch is energy storage, something its structure is especially suited for, because:

1. Starch is insoluble and therefore doesn’t what?

Answer 7

Starch:

1. Is insoluble
2. Therefore doesn’t affect water potential

Question 8

The main role of starch is energy storage, something its structure is especially suited for, because:

1. Starch is insoluble and therefore doesn’t affect water potential, so water is not what?

Answer 8

The main role of starch is energy storage, something its structure is especially suited for, because starch:

1. Is insoluble
2. Therefore doesn’t affect water potential

,so water is not drawn into the cells by osmosis

Question 9

The main role of starch is energy storage, something its structure is especially suited for, because:

1. Starch is insoluble and therefore doesn’t affect water potential, so water is not drawn into the cells by osmosis.
2. Being large and insoluble, starch does not what?

Answer 9

The main role of starch is energy storage, something its structure is especially suited for, because being:

1. Large
2. Insoluble

,starch does not diffuse out of cells

Question 10

The main role of starch is energy storage, something its structure is especially suited for, because:

1. Starch is insoluble and therefore doesn’t affect water potential, so water is not drawn into the cells by osmosis.
2. Being large and insoluble, starch does not diffuse out of cells.
3. Starch is compact, so what?

Answer 10

The main role of starch is energy storage, something its structure is especially suited for, because starch is compact, so a lot of it can be stored in a small space

Question 11

The main role of starch is energy storage, something its structure is especially suited for, because:

1. Starch is insoluble and therefore doesn’t affect water potential, so water is not drawn into the cells by osmosis.
2. Being large and insoluble, starch does not diffuse out of cells.
3. Starch is compact, so a lot of it can be stored in a small space.
4. When hydrolysed, starch forms what?

Answer 11

The main role of starch is energy storage, something its structure is especially suited for, because when hydrolysed, starch forms a-glucose

Question 12

The main role of starch is energy storage, something its structure is especially suited for, because:

1. Starch is insoluble and therefore doesn’t affect water potential, so water is not drawn into the cells by osmosis.
2. Being large and insoluble, starch does not diffuse out of cells.
3. Starch is compact, so a lot of it can be stored in a small space.
4. When hydrolysed, starch forms a-glucose, which is both what?

Answer 12

The main role of starch is energy storage, something its structure is especially suited for, because when hydrolysed, starch forms a-glucose, which is both:

1. Easily transported
2. Readily used in respiration

Question 13

The main role of starch is energy storage, something its structure is especially suited for, because:

1. Starch is insoluble and therefore doesn’t affect water potential, so water is not drawn into the cells by osmosis.
2. Being large and insoluble, starch does not diffuse out of cells.
3. Starch is compact, so a lot of it can be stored in a small space.
4. When hydrolysed, starch forms a-glucose, which is both easily transported and readily used in respiration.
5. The branched form of starch has many what?

Answer 13

The main role of starch is energy storage, something its structure is especially suited for, because the branched form of starch has many ends

Question 14

The main role of starch is energy storage, something its structure is especially suited for, because:

1. Starch is insoluble and therefore doesn’t affect water potential, so water is not drawn into the cells by osmosis.
2. Being large and insoluble, starch does not diffuse out of cells.
3. Starch is compact, so a lot of it can be stored in a small space.
4. When hydrolysed, starch forms a-glucose, which is both easily transported and readily used in respiration.
5. The branched form of starch has many ends, each of which can be what?

Answer 14

The main role of starch is energy storage, something its structure is especially suited for, because the branched form of starch has many ends, each of which can be acted on by enzymes simultaneously

Question 15

The main role of starch is energy storage, something its structure is especially suited for, because:

1. Starch is insoluble and therefore doesn’t affect water potential, so water is not drawn into the cells by osmosis.
2. Being large and insoluble, starch does not diffuse out of cells.
3. Starch is compact, so a lot of it can be stored in a small space.
4. When hydrolysed, starch forms a-glucose, which is both easily transported and readily used in respiration.
5. The branched form of starch has many ends, each of which can be acted on by enzymes simultaneously, meaning that what?

Answer 15

The main role of starch is energy storage, something its structure is especially suited for, because the branched form of starch has many ends, each of which can be acted on by enzymes simultaneously, meaning that glucose monomers are released very rapidly

Question 16

Starch is never found where?

Answer 16

Starch is never found in animal cells

Question 17

Starch is never found in animal cells. Instead a similar what, called what, does what?

Answer 17

Instead a similar polysaccharide, called glycogen, serves the same role

Question 18

Glycogen is found where?

Answer 18

Glycogen is found in:

1. Animals
2. Bacteria

Question 19

Glycogen is found in animals and bacteria, but never where?

Answer 19

Glycogen is found in:

1. Animals
2. Bacteria

,but never in plant cells

Question 20

Glycogen is found in animals and bacteria, but never in plant cells.

Glycogen is very similar in structure to starch, but what?

Answer 20

Glycogen is very similar in structure to starch, but:

1. Has shorter chains
2. Is more highly branched

Question 21

Glycogen is found in animals and bacteria, but never in plant cells.

Glycogen is very similar in structure to starch, but has shorter chains and is more highly branched.

It is sometimes called ‘animal starch,’ because it is what?

Answer 21

Glycogen is sometimes called ‘animal starch,’ because it is the major carbohydrate storage product of animals

Question 22

Glycogen is found in animals and bacteria, but never in plant cells.

Glycogen is very similar in structure to starch, but has shorter chains and is more highly branched.

It is sometimes called ‘animal starch,’ because it is the major carbohydrate storage product of animals.

In animals, glycogen is stored as what?

Answer 22

In animals, glycogen is stored as small granules

Question 23

Glycogen is found in animals and bacteria, but never in plant cells.

Glycogen is very similar in structure to starch, but has shorter chains and is more highly branched.

It is sometimes called ‘animal starch,’ because it is the major carbohydrate storage product of animals.

In animals, glycogen is stored as small granules, mainly where?

Answer 23

In animals, glycogen is stored as small granules, mainly in the:

1. Muscles
2. Liver

Question 24

Glycogen is found in animals and bacteria, but never in plant cells.

Glycogen is very similar in structure to starch, but has shorter chains and is more highly branched.

It is sometimes called ‘animal starch,’ because it is the major carbohydrate storage product of animals.

In animals, glycogen is stored as small granules, mainly in the muscles and the liver.

The mass of carbohydrate that is stored is what?

Answer 24

The mass of carbohydrate that is stored is relatively small

Question 25

Glycogen is found in animals and bacteria, but never in plant cells.

Glycogen is very similar in structure to starch, but has shorter chains and is more highly branched.

It is sometimes called ‘animal starch,’ because it is the major carbohydrate storage product of animals.

In animals, glycogen is stored as small granules, mainly in the muscles and the liver.

The mass of carbohydrate that is stored is relatively small, because what?

Answer 25

The mass of carbohydrate that is stored is relatively small, because fat is the main storage molecule in animals

Question 26

Glycogen’s structure is suited for storage, because:

1. It is insoluble and therefore does not tend to do what?

Answer 26

Glycogen’s structure is suited for storage, because glycogen:

1. Is insoluble
2. Therefore does not tend to draw water into the cells by osmosis

Question 27

Glycogen’s structure is suited for storage, because:

1. It is insoluble and therefore does not tend to draw water into the cells by osmosis.
2. Being insoluble, it does not do what?

Answer 27

Glycogen’s structure is suited for storage, because being insoluble, glycogen does not diffuse out of cells

Question 28

Glycogen’s structure is suited for storage, because:

1. It is insoluble and therefore does not tend to draw water into the cells by osmosis.
2. Being insoluble, glycogen does not diffuse out of cells.
3. It is compact, so what?

Answer 28

Glycogen’s structure is suited for storage, because glycogen is compact, so a lot of it can be stored in a small space

Question 29

Glycogen’s structure is suited for storage, because:

1. It is insoluble and therefore does not tend to draw water into the cells by osmosis.
2. Being insoluble, glycogen does not diffuse out of cells.
3. Glycogen is compact, so a lot of it can be stored in a small space.
4. It is more what than starch?

Answer 29

Glycogen’s structure is suited for storage, because glycogen is more highly branched than starch

Question 30

Glycogen’s structure is suited for storage, because:

1. It is insoluble and therefore does not tend to draw water into the cells by osmosis.
2. Being insoluble, glycogen does not diffuse out of cells.
3. Glycogen is compact, so a lot of it can be stored in a small space.
4. It is more highly branched than starch and so has more ends that can be what?

Answer 30

Glycogen’s structure is suited for storage, because glycogen:

1. Is more highly branched than starch
2. So has more ends that can be acted on simultaneously by enzymes

Question 31

Glycogen’s structure is suited for storage, because:

1. It is insoluble and therefore does not tend to draw water into the cells by osmosis.
2. Being insoluble, glycogen does not diffuse out of cells.
3. Glycogen is compact, so a lot of it can be stored in a small space.
4. It is more highly branched than starch and so has more ends that can be acted on simultaneously by enzymes.

It is therefore more rapidly what?

Answer 31

Glycogen is therefore more rapidly broken down to form glucose monomers

Question 32

Glycogen’s structure is suited for storage, because:

1. It is insoluble and therefore does not tend to draw water into the cells by osmosis.
2. Being insoluble, glycogen does not diffuse out of cells.
3. Glycogen is compact, so a lot of it can be stored in a small space.
4. It is more highly branched than starch and so has more ends that can be acted on simultaneously by enzymes.

It is therefore more rapidly broken down to form glucose monomers, which are used where?

Answer 32

Glycogen is therefore more rapidly broken down to form glucose monomers, which are used in respiration

Question 33

Glycogen’s structure is suited for storage, because:

1. It is insoluble and therefore does not tend to draw water into the cells by osmosis.
2. Being insoluble, glycogen does not diffuse out of cells.
3. Glycogen is compact, so a lot of it can be stored in a small space.
4. It is more highly branched than starch and so has more ends that can be acted on simultaneously by enzymes.

It is therefore more rapidly broken down to form glucose monomers, which are used in respiration.

This is important to animals that have what than plants?

Answer 33

This is important to animals that have a higher:

1. Metabolic rate
2. Therefore respiratory rate

than plants

Question 34

Glycogen’s structure is suited for storage, because:

1. It is insoluble and therefore does not tend to draw water into the cells by osmosis.
2. Being insoluble, glycogen does not diffuse out of cells.
3. Glycogen is compact, so a lot of it can be stored in a small space.
4. It is more highly branched than starch and so has more ends that can be acted on simultaneously by enzymes.

It is therefore more rapidly broken down to form glucose monomers, which are used in respiration.

This is important to animals that have a higher metabolic rate and therefore respiratory rate than plants, because they are more what?

Answer 34

This is important to animals that have a higher:

1. Metabolic rate
2. Therefore respiratory rate

than plants, because they are more active

Question 35

Cellulose differs from starch and glycogen in one major respect:

It is made of what, rather than what?

Answer 35

Cellulose is made of monomers of:

1. B-glucose

,rather than

2. a-glucose

Question 36

Cellulose differs from starch and glycogen in one major respect:

It is made of monomers of B-glucose, rather than a-glucose.

This seemingly small variation produces what?

Answer 36

This seemingly small variation produces fundamental differences in the:

1. Structure
2. Function

of this polysaccharide

Question 37

Cellulose differs from starch and glycogen in one major respect:

It is made of monomers of B-glucose, rather than a-glucose.

This seemingly small variation produces fundamental differences in the structure and function of this polysaccharide.

Rather than forming a coiled chain like starch, cellulose has what chains?

Answer 37

Rather than forming a coiled chain like starch, cellulose has:

1. Straight
2. Unbranched

chains

Question 38

Cellulose differs from starch and glycogen in one major respect:

It is made of monomers of B-glucose, rather than a-glucose.

This seemingly small variation produces fundamental differences in the structure and function of this polysaccharide.

Rather than forming a coiled chain like starch, cellulose has straight, unbranched chains.

These do what, allowing what?

Answer 38

These straight, unbranched chains run parallel to one another, allowing hydrogen bonds to form cross-linkages between adjacent chains

Question 39

Cellulose differs from starch and glycogen in one major respect:

It is made of monomers of B-glucose, rather than a-glucose.

This seemingly small variation produces fundamental differences in the structure and function of this polysaccharide.

Rather than forming a coiled chain like starch, cellulose has straight, unbranched chains.

These run parallel to one another, allowing hydrogen bonds to form cross-linkages between adjacent chains.

Each individual hydrogen bond adds what to the strength of the molecule?

Answer 39

Each individual hydrogen bond adds very little to the strength of the molecule

Question 40

Cellulose differs from starch and glycogen in one major respect:

It is made of monomers of B-glucose, rather than a-glucose.

This seemingly small variation produces fundamental differences in the structure and function of this polysaccharide.

Rather than forming a coiled chain like starch, cellulose has straight, unbranched chains.

These run parallel to one another, allowing hydrogen bonds to form cross-linkages between adjacent chains.

While each individual hydrogen bond adds very little to the strength of the molecule, what makes a considerable contribution to strengthening cellulose?

Answer 40

While each individual hydrogen bond adds very little to the strength of the molecule, the sheer overall number of them makes a considerable contribution to strengthening cellulose

Question 41

Cellulose differs from starch and glycogen in one major respect:

It is made of monomers of B-glucose, rather than a-glucose.

This seemingly small variation produces fundamental differences in the structure and function of this polysaccharide.

Rather than forming a coiled chain like starch, cellulose has straight, unbranched chains.

These run parallel to one another, allowing hydrogen bonds to form cross-linkages between adjacent chains.

While each individual hydrogen bond adds very little to the strength of the molecule, the sheer overall number of them makes a considerable contribution to strengthening cellulose, making cellulose what?

Answer 41

While each individual hydrogen bond adds very little to the strength of the molecule, the sheer overall number of them makes a considerable contribution to strengthening cellulose, making cellulose the valuable structural material that it is

Question 42

The cellulose chain, unlike that of starch, has adjacent glucose molecules rotated by what?

Answer 42

The cellulose chain, unlike that of starch, has adjacent glucose molecules rotated by 180 degrees

Question 43

The cellulose chain, unlike that of starch, has adjacent glucose molecules rotated by 180 degrees.

This allows hydrogen bonds to be formed between what that help to give cellulose its structural stability?

Answer 43

This allows hydrogen bonds to be formed between the hydroxyl (-OH) groups on adjacent parallel chains that help to give cellulose its structural stability

Question 44

The cellulose molecules are grouped together to form what?

Answer 44

The cellulose molecules are grouped together to form microfibrils

Question 45

The cellulose molecules are grouped together to form microfibrils, which, in turn, are what?

Answer 45

The cellulose molecules are grouped together to form microfibrils, which, in turn, are arranged in parallel groups called fibres

Question 46

The cellulose molecules are grouped together to form microfibrils, which, in turn, are arranged in parallel groups called fibres.

Cellulose is a major component of plant cell walls and provides what to the plant cell?

Answer 46

Cellulose:

1. Is a major component of plant cell walls
2. Provides rigidity to the plant cell

Question 47

The cellulose molecules are grouped together to form microfibrils, which, in turn, are arranged in parallel groups called fibres.

Cellulose is a major component of plant cell walls and provides rigidity to the plant cell.

The cellulose cell wall also prevents the cell from doing what as water enters it by osmosis?

Answer 47

The cellulose cell wall also prevents the cell from bursting as water enters it by osmosis

Question 48

The cellulose molecules are grouped together to form microfibrils, which, in turn, are arranged in parallel groups called fibres.

Cellulose is a major component of plant cell walls and provides rigidity to the plant cell.

The cellulose cell wall also prevents the cell from bursting as water enters it by osmosis.

It does this by doing what?

Answer 48

The cellulose cell wall also prevents the cell from bursting as water enters it by osmosis by exerting an inward pressure that stops any further influx of water

Question 49

The cellulose molecules are grouped together to form microfibrils, which, in turn, are arranged in parallel groups called fibres.

Cellulose is a major component of plant cell walls and provides rigidity to the plant cell.

The cellulose cell wall also prevents the cell from bursting as water enters it by osmosis.

It does this by exerting an inward pressure that stops any further influx of water.

As a result, living plant cells are what?

Answer 49

As a result, living plant cells are turgid

Question 50

The cellulose molecules are grouped together to form microfibrils, which, in turn, are arranged in parallel groups called fibres.

Cellulose is a major component of plant cell walls and provides rigidity to the plant cell.

The cellulose cell wall also prevents the cell from bursting as water enters it by osmosis.

It does this by exerting an inward pressure that stops any further influx of water.

As a result, living plant cells are turgid and do what?

Answer 50

As a result, living plant cells:

1. Are turgid
2. Push against one another

Question 51

The cellulose molecules are grouped together to form microfibrils, which, in turn, are arranged in parallel groups called fibres.

Cellulose is a major component of plant cell walls and provides rigidity to the plant cell.

The cellulose cell wall also prevents the cell from bursting as water enters it by osmosis.

It does this by exerting an inward pressure that stops any further influx of water.

As a result, living plant cells are turgid and push against one another, making non-woody parts of the plant what?

Answer 51

As a result, living plant cells:

1. Are turgid
2. Push against one another

,making non-woody parts of the plant semi-rigid

Question 52

The cellulose molecules are grouped together to form microfibrils, which, in turn, are arranged in parallel groups called fibres.

Cellulose is a major component of plant cell walls and provides rigidity to the plant cell.

The cellulose cell wall also prevents the cell from bursting as water enters it by osmosis.

It does this by exerting an inward pressure that stops any further influx of water.

As a result, living plant cells are turgid and push against one another, making non-woody parts of the plant semi-rigid.

This is especially important in doing what?

Answer 52

This is especially important in maintaining:

1. Stems
2. Leaves

in a turgid state

Question 53

The cellulose molecules are grouped together to form microfibrils, which, in turn, are arranged in parallel groups called fibres.

Cellulose is a major component of plant cell walls and provides rigidity to the plant cell.

The cellulose cell wall also prevents the cell from bursting as water enters it by osmosis.

It does this by exerting an inward pressure that stops any further influx of water.

As a result, living plant cells are turgid and push against one another, making non-woody parts of the plant semi-rigid.

This is especially important in maintaining stems and leaves in a turgid state, so that they can do what?

Answer 53

This is especially important in maintaining:

1. Stems
2. Leaves

in a turgid state, so that they can provide the maximum surface area for photosynthesis

Question 54

In summary, the structure of cellulose is suited to its function of providing support and rigidity, because:

1. Cellulose molecules are made up of what?

Answer 54

In summary, the structure of cellulose is suited to its function of providing:

1. Support
2. Rigidity

,because cellulose molecules are made up of B-glucose

Question 55

In summary, the structure of cellulose is suited to its function of providing support and rigidity, because:

1. Cellulose molecules are made up of B-glucose and so form what chains?

Answer 55

In summary, the structure of cellulose is suited to its function of providing support and rigidity, because cellulose molecules are made up of B-glucose and so form:

1. Long
2. Straight
3. Unbranched

chains

Question 56

In summary, the structure of cellulose is suited to its function of providing support and rigidity, because:

1. Cellulose molecules are made up of B-glucose and so form long, straight and unbranched chains.
2. These cellulose molecular chains run how?

Answer 56

In summary, the structure of cellulose is suited to its function of providing support and rigidity, because these cellular molecular chains run parallel to each other

Question 57

In summary, the structure of cellulose is suited to its function of providing support and rigidity, because:

1. Cellulose molecules are made up of B-glucose and so form long, straight and unbranched chains.
2. These cellulose molecular chains run parallel to each other and are crossed by hydrogen bonds which add what?

Answer 57

In summary, the structure of cellulose is suited to its function of providing support and rigidity, because these cellular molecular chains:

1. Run parallel to each other
2. Are crossed by hydrogen bonds which add collective strength

Question 58

In summary, the structure of cellulose is suited to its function of providing support and rigidity, because:

1. Cellulose molecules are made up of B-glucose and so form long, straight and unbranched chains.
2. These cellulose molecular chains run parallel to each other and are crossed by hydrogen bonds which add collective strength.
3. These molecules are grouped to form what?

Answer 58

In summary, the structure of cellulose is suited to its function of providing:

1. Support
2. Rigidity

,because these molecules are grouped to form microfibrils

Question 59

In summary, the structure of cellulose is suited to its function of providing support and rigidity, because:

1. Cellulose molecules are made up of B-glucose and so form long, straight and unbranched chains.
2. These cellulose molecular chains run parallel to each other and are crossed by hydrogen bonds which add collective strength.
3. These molecules are grouped to form microfibrils, which in turn are what?

Answer 59

In summary, the structure of cellulose is suited to its function of providing:

1. Support
2. Rigidity

,because these molecules are grouped to form microfibrils, which in turn are grouped to form fibres

Question 60

In summary, the structure of cellulose is suited to its function of providing support and rigidity, because:

1. Cellulose molecules are made up of B-glucose and so form long, straight and unbranched chains.
2. These cellulose molecular chains run parallel to each other and are crossed by hydrogen bonds which add collective strength.
3. These molecules are grouped to form microfibrils, which in turn are grouped to form microfibrils, which in turn are grouped to form fibres, all of which provides yet more what?

Answer 60

In summary, the structure of cellulose is suited to its function of providing:

1. Support
2. Rigidity

,because these molecules are grouped to form microfibrils, which in turn are grouped to form fibres, all of which provides yet more strength

Question 61

What is the main structural sugar in plants?

Answer 61

Cellulose is the main structural sugar in plants

Question 62

What is about 33% of plant matter?

Answer 62

Cellulose is about 33% of plant matter

Question 63

What is the most common organic compound on Earth?

Answer 63

Cellulose is the most common organic compound on Earth

Question 64

Why can’t humans digest cellulose?

Answer 64

Humans can’t digest cellulose, because we don’t produce the enzyme cellulase

Question 65

Humans can’t digest cellulose, because we don’t produce the enzyme cellulose.

What, like what, have what in their stomachs?

Answer 65

Ruminants, like cows, have symbiotic bacteria in their stomachs

Question 66

The what bonds result in amylopectin having a highly branched structure?

Answer 66

The a-glucose 1 - 6 glycosidic bonds result in amylopectin having a highly branched structure

Question 67

What is 20% of starch?

Answer 67

Amylose (a helix) is 20% of starch

Question 68

What is 80% of starch?

Answer 68

Amylopectin (branched starch) is 80% of starch

Question 69

Amylopectin (branched starch) is 80% of starch.

Amylopectin can be what more quickly than amylose?

Answer 69

Amylopectin can be hydrolysed more quickly than amylose

Question 70

Amylopectin (branched starch) is 80% of starch.

Amylopectin can be hydrolysed more quickly than amylose.

What do plants do with amylopectin?

Answer 70

Plants:

1. Store amylopectin
2. Then hydrolyse it

when they need a supply of energy