1.2 Carbohydrates Flashcards
What is a monosaccharide
Are the monomers from which larger carbohydrates are made
What are the 3 main monosaccharides
- Glucose
- Galactose
- Fructose
What 2 monosaccharides only contain 5 carbons
- Ribose
- Deoxyribose
What are the 2 types of glucose
- Alpha
- Beta
How are disaccharides formed
Via condensation reactions
What chemical bond forms between 2 monosaccharides after a condensation reaction
A glycosidic bond
What 2 monosaccharides make up maltose
Glucose + glucose
What 2 monosaccharides make up lactose
Glucose + Galactose
What 2 monosaccharides make up sucrose
Glucose + Fructose
What are the 3 main disaccharides
- Sucrose
- Maltose
- Lactose
What 2 polysaccharides act as a glucose storage
- Starch
- Glycogen
What polysaccharide has a role in structural function
Cellulose
What 2 polysaccharides are polymers of alpha glucose
- Starch
- Glycogen
What is the monomer of cellulose
Beta glucose
Where is starch found
In plants
Where is glycogen found
In animals
Where is cellulose found
In plant cell walls
List 3 properties of sugars
- Sweet
- Soluble
- Crystalline
On this card then draw alpha glucose
How does alpha glucose differ from beta glucose
In alpha glucose the hydroxyl group on carbon 1 is below the carbon, whereas in beta glucose the hydroxyl group on carbon 1 is above the carbon
What is the shape of fructose
Pentagon
How many carbons are in fructose
6
What shape is galactose
Hexagon
How many carbons are in galactose
6
What shape is ribose and deoxyribose
Pentagon
What is the difference between ribose and deoxyribose
In deoxyribose, there is no oxygen on carbon 2.
How many carbons are in ribose and deoxyribose
5 carbons
Why is it beneficial that the polysaccharides of alpha glucose have a compact shape
To store more glucose in cell
Why is it beneficial that the polysaccharides of alpha glucose are branched
To increase the surface area for hydrolysis so faster release of glucose
Why is it beneficial that the polysaccharides of alpha glucose are insoluble in water
So they are osmotically inert, so doesn’t affect the water potential
What are the 2 types of starch called
- Amylose
- Amylopectin
What bonds are in amylose
1-4 glycosidic bonds
What % of starch is amylose
about 30 %
What shape is amylose
Helical (helix)
Why is amylose helical (have a helix shape)
Because all the glycosidic bonds face downwards
What % of starch is amylopectin
about 70%
What bonds are in amylopectin
1-4 and 1-6 glycosidic bonds
What molecule is branched, amylose or amylopectin
Amylopectin, due to the 1-6 glycosidic bonds
Does amylopectin or glycogen contain more 1-6 glycosidic bonds
Glycogen has more 1-6 bonding therefore more branched that amylopectin
Why is glycogen more branched that amylopectin
Because glycogen is found in animals who have a higher metabolic rate than plants (where amylopectin is found) so the more branching more there’s a faster release of glucose during hydrolysis
How are cellulose chains straight
- The glycosidic bonds between the beta glucose molecules alternate facing up and down since every other glucose flips 180 degrees
What holds multiple cellulose chains together
Hydrogen bonds
What type of strength of the hydrogen bonds give in cellulose
High tensile strength
What is a name given to multiple cellulose chains held together by hydrogen bonds
A microfibril
What enzyme hydrolyses starch
Amylase
What enzyme hydrolyses glycogen
Glycogen phosphorylase
Why is it significant that both starch and glycogen are large molecules
- To store more glucose
- So they cannot pass out of the cell
Explain the importance of glucose to an organism
- Glucose is a main respiratory substrate for cells, as it is phosphorylated in glycolysis
- Glucose is used to produce ATP, the universal energy currency of cells
- Glucose also serves as a substrate for the synthesis of other important molecules, such as glycogen and nucleotides
