Biological Molecules Flashcards
What are the 3 main functions of carbohydrates?
- Storage of energy
- Release of energy
- Cellular structures (cellulose cell wall of plant cells)
Why is glucose called a hexose sugar?
Monosaccharide that contains 6 carbon atoms
What’s the difference between alpha and beta glucose?
ABBA (OH group)
Alpha Below
Beta Above
What is an isomer?
Molecules with the same chemical formula but different arrangements of their atoms
What are the 2 other hexose sugars?
Fructose and galactose
What is a property of monosaccharides?
Soluble in water
Due to small size so easily dissolve in cell and are easily transported in the bloodstream
Alpha glucose + alpha glucose =
Maltose
Glucose + fructose =
Sucrose
Glucose + galactose =
Lactose
What’s the name of the bond between the 2 sugars in a disaccharide?
Glycosidic
How can disaccharides be broken back down to monosaccharides?
Hydrolysis reaction
(Breaking of the glycosidic bond by chemically inserting water)
Properties of polysaccharides eg starch (ICE)
- INSOLUBLE so don’t affect osmosis
- COMPACT so can be stored in small placed in the cell/can store a lot in one area
- EASILY HYDROLYSED to release the glucose for respiration
Give 4 examples of polysaccharides
- STARCH (storage in plants)
- GLYCOGEN (storage in animals)
- CELLULOSE (structural in plants)
- CHITIN (structural in animals)
Are storage polysaccharides alpha or beta glucose?
Alpha
Are structural polysaccharides alpha or beta glucose?
Beta
(Beat it and it will keep its shape)
What 2 molecules make up starch?
Amylose and amylopectin
Describe the structure of amylose
Straight chained, helical polymer containing alpha 1-4 glycosidic bonds
Describe the structure of amylopectin
Branched polymer containing alpha 1-4 and alpha 1-6 glycosidic bonds
Where is glycogen stored?
Liver and muscle cells
Describe the structure of glycogen
Highly branched polymer containing alpha 1-4 and alpha 1-6 glycosidic bonds
Describe the structure of cellulose
- Beta glucose monomers joined by 1-4 glycosidic bonds
- Each adjacent beta glucose monomer rotated 180
- Forming straight chains
- Hydrogen bonds form between OH groups of straight chains
- Many straight chains joined together by many hydrogen bonds forms a strong microfibril