1.4: Starch, glycogen and cellulose Flashcards
Starch is a polysaccharide that is found in many parts of a plant in the form of small grains.
Especially large amounts occur where?
Especially large amounts of starch occur in:
- Seeds
- Storage organs
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?
Especially large amounts of starch occur in:
- Seeds
- Storage organs, such as potato tubers
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?
The chains of a-glucose monosaccharides linked by glycosidic bonds may be:
- Branched
Or,
- Unbranched
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?
The unbranched chain is wound into a tight coil that makes the molecule very compact
The main role of starch is what?
The main role of starch is energy storage
The main role of starch is energy storage, something its structure is what?
The main role of starch is energy storage, something its structure is especially suited for
The main role of starch is energy storage, something its structure is especially suited for, because:
- Starch is insoluble and therefore doesn’t what?
Starch:
- Is insoluble
- Therefore doesn’t affect water potential
The main role of starch is energy storage, something its structure is especially suited for, because:
- Starch is insoluble and therefore doesn’t affect water potential, so water is not what?
The main role of starch is energy storage, something its structure is especially suited for, because starch:
- Is insoluble
- Therefore doesn’t affect water potential
,so water is not drawn into the cells by osmosis
The main role of starch is energy storage, something its structure is especially suited for, because:
- Starch is insoluble and therefore doesn’t affect water potential, so water is not drawn into the cells by osmosis.
- Being large and insoluble, starch does not what?
The main role of starch is energy storage, something its structure is especially suited for, because being:
- Large
- Insoluble
,starch does not diffuse out of cells
The main role of starch is energy storage, something its structure is especially suited for, because:
- Starch is insoluble and therefore doesn’t affect water potential, so water is not drawn into the cells by osmosis.
- Being large and insoluble, starch does not diffuse out of cells.
- Starch is compact, so what?
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
The main role of starch is energy storage, something its structure is especially suited for, because:
- Starch is insoluble and therefore doesn’t affect water potential, so water is not drawn into the cells by osmosis.
- Being large and insoluble, starch does not diffuse out of cells.
- Starch is compact, so a lot of it can be stored in a small space.
- When hydrolysed, starch forms what?
The main role of starch is energy storage, something its structure is especially suited for, because when hydrolysed, starch forms a-glucose
The main role of starch is energy storage, something its structure is especially suited for, because:
- Starch is insoluble and therefore doesn’t affect water potential, so water is not drawn into the cells by osmosis.
- Being large and insoluble, starch does not diffuse out of cells.
- Starch is compact, so a lot of it can be stored in a small space.
- When hydrolysed, starch forms a-glucose, which is both what?
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:
- Easily transported
- Readily used in respiration
The main role of starch is energy storage, something its structure is especially suited for, because:
- Starch is insoluble and therefore doesn’t affect water potential, so water is not drawn into the cells by osmosis.
- Being large and insoluble, starch does not diffuse out of cells.
- Starch is compact, so a lot of it can be stored in a small space.
- When hydrolysed, starch forms a-glucose, which is both easily transported and readily used in respiration.
- The branched form of starch has many what?
The main role of starch is energy storage, something its structure is especially suited for, because the branched form of starch has many ends
The main role of starch is energy storage, something its structure is especially suited for, because:
- Starch is insoluble and therefore doesn’t affect water potential, so water is not drawn into the cells by osmosis.
- Being large and insoluble, starch does not diffuse out of cells.
- Starch is compact, so a lot of it can be stored in a small space.
- When hydrolysed, starch forms a-glucose, which is both easily transported and readily used in respiration.
- The branched form of starch has many ends, each of which can be what?
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
The main role of starch is energy storage, something its structure is especially suited for, because:
- Starch is insoluble and therefore doesn’t affect water potential, so water is not drawn into the cells by osmosis.
- Being large and insoluble, starch does not diffuse out of cells.
- Starch is compact, so a lot of it can be stored in a small space.
- When hydrolysed, starch forms a-glucose, which is both easily transported and readily used in respiration.
- The branched form of starch has many ends, each of which can be acted on by enzymes simultaneously, meaning that what?
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
Starch is never found where?
Starch is never found in animal cells
Starch is never found in animal cells. Instead a similar what, called what, does what?
Instead a similar polysaccharide, called glycogen, serves the same role
Glycogen is found where?
Glycogen is found in:
- Animals
- Bacteria
Glycogen is found in animals and bacteria, but never where?
Glycogen is found in:
- Animals
- Bacteria
,but never in plant cells
Glycogen is found in animals and bacteria, but never in plant cells.
Glycogen is very similar in structure to starch, but what?
Glycogen is very similar in structure to starch, but:
- Has shorter chains
- Is more highly branched
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?
Glycogen is sometimes called ‘animal starch,’ because it is the major carbohydrate storage product of animals
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?
In animals, glycogen is stored as small granules
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?
In animals, glycogen is stored as small granules, mainly in the:
- Muscles
- Liver
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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?
The mass of carbohydrate that is stored is relatively small
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?
The mass of carbohydrate that is stored is relatively small, because fat is the main storage molecule in animals
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Glycogen’s structure is suited for storage, because:
- It is insoluble and therefore does not tend to do what?
Glycogen’s structure is suited for storage, because glycogen:
- Is insoluble
- Therefore does not tend to draw water into the cells by osmosis
Glycogen’s structure is suited for storage, because:
- It is insoluble and therefore does not tend to draw water into the cells by osmosis.
- Being insoluble, it does not do what?
Glycogen’s structure is suited for storage, because being insoluble, glycogen does not diffuse out of cells
Glycogen’s structure is suited for storage, because:
- It is insoluble and therefore does not tend to draw water into the cells by osmosis.
- Being insoluble, glycogen does not diffuse out of cells.
- It is compact, so what?
Glycogen’s structure is suited for storage, because glycogen is compact, so a lot of it can be stored in a small space
Glycogen’s structure is suited for storage, because:
- It is insoluble and therefore does not tend to draw water into the cells by osmosis.
- Being insoluble, glycogen does not diffuse out of cells.
- Glycogen is compact, so a lot of it can be stored in a small space.
- It is more what than starch?
Glycogen’s structure is suited for storage, because glycogen is more highly branched than starch
Glycogen’s structure is suited for storage, because:
- It is insoluble and therefore does not tend to draw water into the cells by osmosis.
- Being insoluble, glycogen does not diffuse out of cells.
- Glycogen is compact, so a lot of it can be stored in a small space.
- It is more highly branched than starch and so has more ends that can be what?
Glycogen’s structure is suited for storage, because glycogen:
- Is more highly branched than starch
- So has more ends that can be acted on simultaneously by enzymes
Glycogen’s structure is suited for storage, because:
- It is insoluble and therefore does not tend to draw water into the cells by osmosis.
- Being insoluble, glycogen does not diffuse out of cells.
- Glycogen is compact, so a lot of it can be stored in a small space.
- 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?
Glycogen is therefore more rapidly broken down to form glucose monomers
Glycogen’s structure is suited for storage, because:
- It is insoluble and therefore does not tend to draw water into the cells by osmosis.
- Being insoluble, glycogen does not diffuse out of cells.
- Glycogen is compact, so a lot of it can be stored in a small space.
- 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?
Glycogen is therefore more rapidly broken down to form glucose monomers, which are used in respiration
Glycogen’s structure is suited for storage, because:
- It is insoluble and therefore does not tend to draw water into the cells by osmosis.
- Being insoluble, glycogen does not diffuse out of cells.
- Glycogen is compact, so a lot of it can be stored in a small space.
- 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?
This is important to animals that have a higher:
- Metabolic rate
- Therefore respiratory rate
than plants
Glycogen’s structure is suited for storage, because:
- It is insoluble and therefore does not tend to draw water into the cells by osmosis.
- Being insoluble, glycogen does not diffuse out of cells.
- Glycogen is compact, so a lot of it can be stored in a small space.
- 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?
This is important to animals that have a higher:
- Metabolic rate
- Therefore respiratory rate
than plants, because they are more active
Cellulose differs from starch and glycogen in one major respect:
It is made of what, rather than what?
Cellulose is made of monomers of:
- B-glucose
,rather than
- a-glucose
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?
This seemingly small variation produces fundamental differences in the:
- Structure
- Function
of this polysaccharide
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?
Rather than forming a coiled chain like starch, cellulose has:
- Straight
- Unbranched
chains
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?
These straight, unbranched chains run parallel to one another, allowing hydrogen bonds to form cross-linkages between adjacent chains
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?
Each individual hydrogen bond adds very little to the strength of the molecule
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?
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
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?
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
The cellulose chain, unlike that of starch, has adjacent glucose molecules rotated by what?
The cellulose chain, unlike that of starch, has adjacent glucose molecules rotated by 180 degrees
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?
This allows hydrogen bonds to be formed between the hydroxyl (-OH) groups on adjacent parallel chains that help to give cellulose its structural stability
The cellulose molecules are grouped together to form what?
The cellulose molecules are grouped together to form microfibrils
The cellulose molecules are grouped together to form microfibrils, which, in turn, are what?
The cellulose molecules are grouped together to form microfibrils, which, in turn, are arranged in parallel groups called fibres
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?
Cellulose:
- Is a major component of plant cell walls
- Provides rigidity to the plant cell
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?
The cellulose cell wall also prevents the cell from bursting as water enters it by osmosis
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?
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
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?
As a result, living plant cells are turgid
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?
As a result, living plant cells:
- Are turgid
- Push against one another
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?
As a result, living plant cells:
- Are turgid
- Push against one another
,making non-woody parts of the plant semi-rigid
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?
This is especially important in maintaining:
- Stems
- Leaves
in a turgid state
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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?
This is especially important in maintaining:
- Stems
- Leaves
in a turgid state, so that they can provide the maximum surface area for photosynthesis
In summary, the structure of cellulose is suited to its function of providing support and rigidity, because:
- Cellulose molecules are made up of what?
In summary, the structure of cellulose is suited to its function of providing:
- Support
- Rigidity
,because cellulose molecules are made up of B-glucose
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 what chains?
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:
- Long
- Straight
- Unbranched
chains
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 long, straight and unbranched chains.
- These cellulose molecular chains run how?
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
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 long, straight and unbranched chains.
- These cellulose molecular chains run parallel to each other and are crossed by hydrogen bonds which add what?
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
- Are crossed by hydrogen bonds which add collective strength
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 long, straight and unbranched chains.
- These cellulose molecular chains run parallel to each other and are crossed by hydrogen bonds which add collective strength.
- These molecules are grouped to form what?
In summary, the structure of cellulose is suited to its function of providing:
- Support
- Rigidity
,because these molecules are grouped to form microfibrils
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 long, straight and unbranched chains.
- These cellulose molecular chains run parallel to each other and are crossed by hydrogen bonds which add collective strength.
- These molecules are grouped to form microfibrils, which in turn are what?
In summary, the structure of cellulose is suited to its function of providing:
- Support
- Rigidity
,because these molecules are grouped to form microfibrils, which in turn are grouped to form fibres
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 long, straight and unbranched chains.
- These cellulose molecular chains run parallel to each other and are crossed by hydrogen bonds which add collective strength.
- 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?
In summary, the structure of cellulose is suited to its function of providing:
- Support
- Rigidity
,because these molecules are grouped to form microfibrils, which in turn are grouped to form fibres, all of which provides yet more strength
What is the main structural sugar in plants?
Cellulose is the main structural sugar in plants
What is about 33% of plant matter?
Cellulose is about 33% of plant matter
What is the most common organic compound on Earth?
Cellulose is the most common organic compound on Earth
Why can’t humans digest cellulose?
Humans can’t digest cellulose, because we don’t produce the enzyme cellulase
Humans can’t digest cellulose, because we don’t produce the enzyme cellulose.
What, like what, have what in their stomachs?
Ruminants, like cows, have symbiotic bacteria in their stomachs
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The what bonds result in amylopectin having a highly branched structure?
The a-glucose 1 - 6 glycosidic bonds result in amylopectin having a highly branched structure
What is 20% of starch?
Amylose (a helix) is 20% of starch
What is 80% of starch?
Amylopectin (branched starch) is 80% of starch
Amylopectin (branched starch) is 80% of starch.
Amylopectin can be what more quickly than amylose?
Amylopectin can be hydrolysed more quickly than amylose
Amylopectin (branched starch) is 80% of starch.
Amylopectin can be hydrolysed more quickly than amylose.
What do plants do with amylopectin?
Plants:
- Store amylopectin
- Then hydrolyse it
when they need a supply of energy