Chapter 1.22 Carbohydrates 2 Polysaccharides Flashcards
Define oligosaccharides
Molecules with 3-10 monosaccharide units
Define hydrolysis reaction
Reaction where the glycosidic bonds are broken by the addition of water molecule
What is amylose ?
Complex carbohydrate containing only glucose monomers joined by 1-4 glycosidic bonds and forms long in branches chains
What is amylopectin?
Complex carbohydrate made up by glucose monomers joined by 1-4 and 1-6 glycosidic bonds so the molecules branch repeatedly
What is glycogen?
Made of many alpha glucose joined by 1-4 and 1-6 glycosidic bonds giving many side branches
What is cellulose ?
Complex carbohydrate with beta glucose held by 1-4 glycosidic bonds
What are polysaccharides made from ?
Many monosaccharide units joined by glycosidic bonds
Fill the blank. Molecules containing 11 or more monosaccharide are known as ____ ______________
True polysaccharide
Does polysaccharide have a sweet taste?
No
Is polysaccharide ideal storage molecules?
Yes
What 3 structure make polysaccharide a good storage molecules ?
- Form very compact molecules so large number can be stored
- Glycosidic bonds are easily broken, allowing rapid release of monosaccharide units for cellular respiration
- Insoluble so doesn’t affect water potential of cell and osmotic water movements
How is glycosidic bonds between two monosaccharides split?
Hydrolysis reaction. Water is added
How are polysaccharides sugars broken to release energy?
Broken down into shorter and shorter chains until there are eventually single sugars left
Where does hydrolysis reaction take place in?
Place where cellular respiration’s are required
Where does hydrolysis reaction take place?
Gut during digestion, muscle and liver
Fill in the blank. The sugars created in photosynthesis is converted into _____ in plants
Starch
Give two reasons which explain why starch is a good for storage molecule
- Insoluble so doesn’t affect the water potential
2. Compact but can be broken down rapidly to release glucose when needed
What is starch made of ?
Long chains of alpha glucose
What 2 compounds is starch made of ?
Amylose and amylopectin
What is amylose ?
Unbranched polymer. As the length increases, it spirals and makes it more compact for storage
What is amylopectin ?
Branches polymer of glucose molecules. The branching chain have many terminating glucose molecules that can be broken off rapidly
In amylose where is glycosidic bond formed ?
1-4 carbons
In amylopectin where are glycosidic bonds created ?
1-4 and 1-6 carbons
Why is eating food that contains starch good for when doing sport?
Amylose release energy slowly over a long period and amylopectin releases energy rapidly
Where is glycogen found in ?
Animals and fungi
What is glycogen made up of ?
Many alpha glucose
True of false. Glycogen has 1-4 as well as 1-6 glycosidic bonds
True. Which is why it is branches and can give energy off rapidly
Where is glycogen found ?
Places where it requires high rate of respiration like muscle and liver tissue
True or false. Starch is the main energy source in plants
True
What percentage of starch does a plant cell contains
70-80 amylopectin and rest of amylose
Give the job of cell wall
Gives plants strength and support
What is cell wall made up of ?
Insoluble cellulose
Describe the structure of cellulose
Long chain of beta glucose joined by glycosidic bonds 1-4
True or false. In cellulose one beta glucose has to be inverted for the 1-4 bonds to take place
True
Why does one beta glucose needs to be inverted for 1-4 glycosidic bonds in cellulose ?
So that hydroxyl (-OH) groups stick out on both sides of the molecule so hydrogen bonds can form between the partially positively charged hydrogen atoms of the hydroxyl groups and the partially negatively charged oxygen atoms in the other areas of the glucose molecules
Does cross linking take place in cellulose ?
Yes it’s the hydrogen bond that acts as the cross link
What makes cellulose strong?
Hydrogen bonds
Does cellulose spiral or coil ?
No they remain very long and straight
True or false. Starch molecules with 1-4 and 1-6 glycosidic bonds between alpha glucose form compact globular molecules that are useful for storage?
True
Fill in the blank. The difference in structure between starch and cellulose gives them very different _________ and _________
Properties. Functions
Why can’t most animals digest cellulose ?
Because it cannot digest 1-4 glycosidic bonds between beta glucose
Fill in the blanks. Ruminants such as sheep and cows have ________, _____ and_______ living in their gut which produce cellulose _________ enzymes
Bacterial, fungi, Protozoa and digesting
