carbohydrates Flashcards
what are monomers?
Monomers are smaller unit which can create larger molecules
name the elements present in carbohydrates
Carbon, hydrogen and oxygen
name carbohydrates that are monomers
Glucose Fructose Galactose
name carbohydrates that are polymers
starch Cellulose Glycogen
What is glucose?
A very important monossaccharide, that is a hexose sugar and has the formula of C6H12O6. And two isomers.
alpha glucose
both OH at the bottom
beta glucose
one OH at top and the other OH at bottom
How could you test if a food contained reducing sugars?
Conduct benedict’s test
Add 2 cm3 of the food sample to be tested in a test tube. If the sample is not in a liquid form already, grind it in water. Add an equal volume of Benedict’s reagent and lastly heat the mixture gently in a water bath for five minutes
Which molecules are reducing sugars? And why?
All monosaccharides and most disaccharides except sucrose. Because they reduce ions
Colour of reducing sugars test if positive
Orange brown
What are disaccharides?
Two monosaccharides joined together by a glycosidic bond, during a condensation reaction with the formation and release of water
Disaccharides example
Glucose+glucose= maltose (+water)
Glucose+galactose= lactose (+water)
Glucose+fructose= sucrose (+water)
What is a condensation reaction?
A reaction that joins up molecules together with the release of water
What is a hydrolysis reaction?
A hydrolysis reaction is a reaction that divides and splits apart 2 molecules by breaking the chemical bonds with the use of water molecule
What is starch and where is it found and what is its function?
Starch is a polysaccharide formed by amylose and amylopectin ( both are two polymers of alpha glucose).
Starch is found in grains in plants, for example inside chloroplast. And its function it is an insoloble store of glucose. This is important because Glucose is soluble in water, so if it is stored in plant cells i can affects the way water moves into and out of cells. Starch is insoluble so has no effect on the water balance in plant cells.
What are polymers?
Polymers are larger molecules which are made up of smaller unit called monomers bonded together
What are the two polymers/polysaccharides that make starch?
Amylopectin(branched) and
Amylose(straight chain,not branched)
What is glycogen made out of? And where is it found?
Made from alpha glucose and found in muscle and liver cells on animals
What is glycogen made out of? And where is it found?
Made from alpha glucose and found in muscle and liver cells on animals
What type of reaction forms glycogen and what type of bonds are present?
A condensation reaction many 2 type f bonds between the alpha molecules. The bonds present are 1,4 glycosidic bonds and a lot more 1,6 glycosidic bonds
What is cellulose made out of ? And where is it found?
Made up of beta glucose and it is found in plant cell wall
What is the structure of cellulose? What type of bonds are there and what type of reaction forms
A condesation reactions forms the Cellulose molecule, which contains only 1,4 glycosidic bonds. Cellulose is now in straight polymer chains of beta glucose. The long chains then lie parallel held together by many hydrogen bonds
Whats the function of cellulose and how does it relate to its structure?
It’s function is to provide structure strenght to the cell wall. it does this by the presence of many hydroggen bonds which provide collective strenght to the cell wall. It is also insoluble and does not dissolve in water.
