Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
19 Cards in this Set
- Front
- Back
What are carbohydrates made up of?
|
Units of sugar
|
|
How many units of sugar does glucose have?
|
one |
|
What type of sugars are glucose and sucrose? |
Simple sugars
|
|
How can you test for starch? |
Using the iodine test. Iodine turns blue/black in the presence of starch |
|
How can you test for glucose?
|
Benedict's test for glucose. Benedict's solution turns from blue to orange. |
|
What are complex carbohydrates?
|
Made up of long chains of simple sugars bonded together, (e.g. starch and cellulose) |
|
What are lipids made up of? |
Three molecules of fatty acids linked to a molecule of glycerol |
|
How would you test for lipids? |
The test substance is mixed with 2 cm3 of ethanol. An equal volume of distilled water is added. A milky-white emulsion forms if the test substance contains lipids |
|
What are proteins made up of?
|
Long chains of amino acids |
|
What happens if a protein is heated? |
It's shape changes and the protein is denatured |
|
How would you test for proteins? |
Biuret test. Turns a purple colour when mixed with protein. |
|
What are enzymes?
|
The are large proteins and biological catalysts, they speed up reaction. |
|
What is the active site of an enzyme?
|
An area in the enzymes shape where another molecule can fit. The substrate in a reaction can be held in the active site and either connected to another molecule or broken down.
|
|
What is formed when a substrate fits the active site?
|
The enzyme-substrate complex |
|
Name 3 things enzymes can do |
Change one molecule into another one Break down large molecules into smaller ones |
|
What factors is enzyme activity affected by? |
Temperature and pH |
|
How does the temperate affect enzyme activity? |
Higher temperatures cause reactions to take place faster. Too high temperatures denature the enzyme, changing the shape of the active site. |
|
Where are digestive enzymes produced?
|
By specialised cells in glands and the lining of the gut. |
|
How are enzymes produced by microorganisms used in industry? |
Proteases predigest some baby foods. isomerase is used to convert glucose syrup into fructose syrup. Carbohydrases are used to convert starch into sugar syrup. |