1.4- Starch, glycogen and cellulose Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is Starch and it’s role?

A

Starch is a polysaccharide that stores energy in plant- large amounts occur in seeds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What type of chains is starch made from?

A

alpha glucose monosaccharides linked by glycosidic bonds that are formed by condensation reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Are starch chains branched or unbranched?

A

Starch chains ,may be branched or unbranched, the unbranched chain is wound into a tight coil that makes the molecule very compact

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The main role of starch is energy storage. How is starch suited for this role?

A
  1. Insoluable= doesn’t effect water potential
  2. Compact= a lot of energy can be stored in one space
  3. when hydrolyzed forms alpha glucose= alpha glucose easily transported and used in respiration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What group in starch faces inwards forming hydrogen bonds, in turn holding the helix in place?

A

OH groups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Name 2 key differences between structure of starch and glycogen

A
  1. glycogen has smaller chains
    2.glycogen is more highly branched
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How is glycogen formed?

A

from the condensation of alpha glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is glycogen for and where is it stored?

A

glycogen is a major carbohydrate storage product of animals
stored in muscle and liver cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How does the structure of glycogen suit it’s function for storage?

A
  1. insoluable= doesn’t draw water in by osmosis, does not diffuse out of cells
  2. compact= a lot of it can be stored in small space
    3.more highly branched than starch- has more ends that can be simultaneously acted on by enzymes
    therefore, more rapidly broken down to form glucose monomers, used in respiration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why is it important that glycogen can be rapidly broken down into glucose monomers which are used in respiration?

A

Animals have a higher metabolic rate and therefore higher respiratory rate than plants because they are more active

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is cellulose made from?

A

beta glucose monomers joined by glycosidic bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is different about the structure of Cellulose as oppose to Starch and Glycogen?

A

Cellulose has straight unbranched chains that run parallel to each other allowing hydrogen bonds to form cross- linkages between adjacent chains as opposed to a coiled chain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is important about these hydrogen bonds in Cellulose?

A

individually hydrogen bonds add little strength however together they make a large contribution to strengthening cellulose, making it a crucial structural material

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Why are adjacent glucose molecules rotated by 180 degrees on a cellulose chain unlike starch?

A

allows hydrogen bonds to be formed between hydroxyl (-OH) groups- help give cellulose structural stability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How is cellulose important in stopping the cell burst under osmotic pressure?

A

exerts inward pressure that stops influx of water - means the cells stay turgid and rigid– helping maximize the surface area of plants for photosynthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What else provides more strength for cellulose?

A

microfibrils- group together to form fibres which provides yet more strength