Carbohydrates Flashcards
finish the sentence
Organic molecules are ones that contain …….
- Carbon
What are monosaccharides?
- Monosaccharides are the monomers from which larger carbohydrates are made
- The single monomer (of sugar) ie. 1 sugar unit.
Monosacchardies = particular sugars
Give 3 examples of monosaccharides?
1.) Glucose
2.) Galactose
3.) Fructose.
How many isomers does glucose have, what are they?
- 2 isomers
- Alpha glucose
- Beta glucose.
What is an isomer?
- Isomer: same molecular formula but different structures.
- Ie. alpha and beta glucose are both isomers of glucose.
What are disaccharides?
- A pair of monosaccharides (ie. two sugar units.)
What are polysaccarides?
- Many monosaccharides joined together.
3 examples of disaccharides.
1.) Sucrose.
2.) Maltose
3.) Lactose.
3 examples of polysaccharides.
1.) Starch.
2.) Cellulose.
3.) Glycogen.
What actually forms a glycosidic bond?
- Condensation reaction between two monosaccharides forms a glycosidic bond.
How are disaccharides formed?
- Disaccharides are formed by the condensation of two
monosaccharides
What are maltose, sucrose and lactose examples of?
- Maltose, sucrose and lactose are examples of dissacharides.
Give the word equation for the condensation reaction of maltose.
glucose + glucose —> maltose+ water
formed by the condesation of two glucose molecules.
Give the word equation for the condensation reaction of sucrose.
glucose + fructose –> sucrose + water
Give the word equation for the condensation reaction of lactose.
glucose + galactose –> lactose + water
How are polysaccharides formed?
- Monosaccharides (ie. glucose units) joined together by glycosidic bonds that were formed from condensation reactions.
What monomer is starch made up of? How are the monomers joined together?
- Many alpha glucose monosacharides join together by glycosidic bonds formed by condensation reactions.
What type of glycosidic bonds are between the alpha glucose monosacharides/ monomers in amylose?
1-4 glycosidic bonds in amylose
Numbers show what part of molecule is bonded to other molecule (labelled numbers - sticky note on wall.)
What type of glycosidic bonds are between the alpha glucose monosacharides/ monomers in amylopectin?
**1-4 and 1-6 **glycosidic bonds in amylopectin.
Numbers show what part of molecule is bonded to other molecule (labelled numbers - sticky note on wall.)
What monomer is cellulose made up of?
- Beta glucose
What type of glycosidic bond is between beta glucose monomers in cellulose?
1-4 glycosidic bonds.
What type of glycosidic bond is between alpha glucose monomers in glycogen?
1-4 and 1-6 glycosidic bonds.
Explain the hydrolysis of a disaccharide?
- Water added to disaccharide.
- Breaks/ hydrolyses glycosidic bond
- Releases monosachrides
Give the function of starch, glycogen and cellulose.
- Starch: store of glucose
- Glycogen: store of glucose.
- Cellulose: Provides structural strength for the cell wall.
What organs is glycogen mainly found in?
- Muscle and liver cells.
Where is starch found?
- Plant cells.
Finish the sentence
Glycogen and starch are formed by the ………. of …….. ……….
- Condensation
- alpha glucose
Finish the sentence
Cellulose is formed by the ……….. of ……. ……..
- Condensation.
- Beta glucose.
What is the structure of starch?
- Mixture of two polysaccharides (bonded together) amylopectin and amylose.
- Amylose: an unbranched helix (1-4 glycosidic bonds.)
- Amylopectin: a branched molecule (1-4 glycosidic bonds AND 1-6 glycosidic bonds.)
() - extra info for clarification
Explain how amylose’s (polysaccharide in starch) structure allows it to carry out its function.
- Helix structure (helical) can compact to store a lot of glucose in a smaller place (ie. allowing for storage of glucose = function of starch.)
Explain how amylopectin’s (component of starch) structure allows it to carry out its function.
- Branched molecule.
- Increases surface area for enzymes to hydrolyse the glycosidic bond - allowing glucose to be released quickly.
How is starch’s structure specially suited for its function of glucose storage?
- It is insoluble (does not affect water potential) so water is not drawn into cells by osmosis.
- Compact.
- The branches: large surface area: so enzymes can attach and hydrolyse the glycosidic bond (ie. for fast enzyme action.)
What is the structure of cellulose?
- Long, straight, unbranched chains
- Chains are held in parallel by hydrogen bonds.
- Hydrogen bonds between the chains form thick fibres called microfibrils (many cellulose chains .)
- Every other beta glucose rotates 180 degrees (ie. position of hydrogen/ hydroxyl groups on carbon atom 1 are inverted) - allows hydrogen bonds to be formed either side - a lot more bonds = more flexibility.
How is cellulose’s structure specially suited for its function of providing structural strength to cell wall?
- Many hydrogen bonds provide collective strength.
- Cellulose –> insoluble (won’t affect water potential.)
What is the structure of glycogen?
- A highly- branched molecule
How is glycogen’s structure specially suited for its function of glucose storage?
- Branched structure, more ends for faster hydrolysis.
- Branched so is compact.
- Insoluble: won’t affect water potential (water won’t be drawn into cell –> cell won’t burst ALONG WITH the glycogen.)
- Glucose polymer so provides respiratory substrate for energy release.
() - extra info in own words for clarification
What makes a polysaccharide branched?
- Its 1-6 glycosidic bonds.
What is the -OH group on monosaccharides known as?
- Hydroxyl group.
What is it called in cellulose when every other glucose is rotated 180 degrees?
- They are **inverted. **
What is the advantage of glycogen, starch and cellulose being insoluble/ not affecting water potential?
- Water won’t be drawn into cells that contain these molecules.
- So the cells won’t burst (along with the starch, cellulose and glycogen.)
