Biological molecules- Carbohydrates Flashcards
What are monomers
Small molecular units that make up polymers
What are polymers
Long chains of monomers joined together
What is a condensation reaction
When a water molecule is released and two molecules join together
Where does a glycosidic bond form
Between two monosaccharides after a molecule of water is released
How is sucrose formed
Glucose and fructose
How is lactose formed
Glucose and galactose
How is glucose formed
Maltose and Maltose
What is a hydrolysis reaction
Breaking the chemical bond between two molecules by adding a water molecule
What is the test for reducing sugars
You add Benedict’s reagent and heat it in a boiled water bath, a positive test will show a colored precipitate ( dependent on strength ) - Red - strong
Blue- Not as strong
What is the test for non reducing sugars
Add dilute HCL and heat it in a boiled water bath then neutralise with sodium hydrogen carbonate and then carry out the Benedict’s test, a positive test is a colored precipitate, a negative test is blue
What is a polysaccharide
More than 2 monosaccharides joined together via condensation reaction
What are the two forms of starch
Amylose and Amylopectin
What are the properties and adaptations of Amylose
- it is a long unbranched chain of alpha glucose
- It has a coiled structure due to the angles of the glycosidic bond
- It is compact and therefore good for storage
What are the properties and adaptations of amylopectin
-It is a long branched chain of alpha glucose
- It has side branches which allow enzymes that break down the molecule to get at the glycosidic bonds easily which means glucose can be released quickly
How do you carry out the iodine test for starch
Add iodine dissolved in potassium iodide to the sample and if starch is present it changes from browny-orange to blue-black
