1.2: Carbohydrates Flashcards
What makes up maltose?
glucose + glucose
What makes up sucrose?
glucose and fructose
What makes up lactose?
glucose + galactose
Draw alpha glucose
Draw beta glucose
What bond joins disaccharides?
glycosidic bond
Where is starch found?
Plants
What are two types of starch
Amylose and amylopectin
What is the structure of amylose? (4)
- Carbon 1:4 glycosidic bond
- long and linear/straight chains
- alpha glucose
- coils into a helix
What is the structure of amylopectin? (3)
- 1:4 and 1:6 carbon glycosidic bonds
- Branched chain
- Alpha glucose
where is glycogen found?
muscle and liver cells in animals
What are the functions of amylose? (3)
- structure is helical so compact and good for storage
- Insoluble so doesn’t affect water potential
- Large so doesn’t diffuse out off cells
What is the structure of glycogen? (3)
- More highly branched
- Shorter chains
- Carbon 1:4 and 1:6 glycosidic bonds
What is the function of amylopectin? (4)
- Large surface area for rapid hydrolysis by enzymes to release glucose for respiration
- Insoluble so doesn’t affect water potential
- Large so doesn’t diffuse out of cells
What is the function of glycogen? (4)
- Large surface area for rapid hydrolysis by enzymes to release glucose for respiration
- Insoluble so doesn’t affect water potential
- Large so doesn’t diffuse out of cells
What is the structure of cellulose? (4)
- Beta glucose joined by condensation reaction
- Long, straight unbranched chains
- Carbon 1:4 glycosidic bonds
- Chains held by many weak hydrogen bonds to form microfibrils
what is the function of cellulose? (2)
- to provide strength and support
- Insoluble so doesn’t affect water potential
Name reducing sugar?
glucose, galactose, fructose, lactose, maltose
Name non-reducing sugar?
sucrose
Test for starch?
1) Add potassium iodide
2) solution turns blue-black
test for reducing sugar?
1) Add Benedict’s reagent
2) heat
3) green/yellow/orange/red precipitate
test for non-reducing sugar?
1) View negative Benedict’s test where reagent stays blue
2) Add acid and boil
3) Cool and neutralise with an alkali
4) Add benedicts and heat
5) Red/orange/yellow/green precipitate
