1.2 Carbohydrates Flashcards
What is the difference between alpha glucose and beta glucose?
The hydroxyl group is flipped in beta glucose
Glucose + glucose
Glucose + galactose
Glucose + fructose
Maltose
Lactose
Sucrose
What is the bond between monosaccharides called?
What reaction causes this bond to form?
How can this bond be be broken?
Glycosidic bond
Condensation reactions where a water molecule is released
Hydrolisis reaction where an enzyme brings a water molecule
What is a polysaccharide?
What are three examples of polysaccharides?
Polymers which are formed when more than 2 monosaccharides join together
Starch in plants
Glycogen in animals
Cellulose in the plant cell walls
What is starch used for?
What is it?
Excess glucose that is stored in plants
A mixture of two polysaccharides of alpha glucose called amylose and amylopectin
What is amylose?
What is its structure?
Long unbranched chain of alpha glucose
Coiled structure that is good for storage as a lot can be fit in a small space
What is amylopectin?
Properties of amylopectin
Long branched chain of alpha glucose
Contains side branches in which the bonds can be broken easily by enzymes - allowing glucose to be released quickly
Why is starch’s insolubility advantageous?
It is insoluble in water and does not affect water potential so water cannot enter via osmosis, preventing turgidity which is good for storage
What is glycogen used for?
What is glycogen?
What are its properties?
Excess glucose stored as glycogen in animals
Polysaccharide of alpha glucose
Similar structure to amylopectin but with more side branches - glucose can be released quickly
Very compact - good for storage
What is cellulose used for?
What is cellulose?
What are its properties?
Structural support in plant cell walls
Long unbranched chain of beta glucose
Beta glucose molecules bonded together to form straight cellulose chains
The cellulose chains are bonded together by H bonds which form strong microfibrils
Reducing sugars test
Sample + benedicts reagent
Heat
Brick red precipitate - blue if not present
Non reducing sugars test
Sample + hydrochloric acid
Heat
Sodium bicarbonate
Benedicts reagent
Reheat
Green , orange to brick red - blue if not present
Test for starch
Sample + iodine
Dark blue
What type of sugar is glucose?
Hexose sugar
