Topic 1 Flashcards
(13 cards)
Test for non-reducing sugars
Heat with acid AND neutralise
Heat with benedicts
Red precipitate
Difference between cellulose and glycogen
Cellulose made of Beta glucose
Glycogen made of alpha glucose
Cellulose has straight chain
Glycogen is branched
Cellulose has straight chain
Glycogen is coiled
Cellulose has 1-4 glycosidic bonds
Glycogen has 1-4 AND 1-6 glycosidic bonds
Features of starch which make it a good storage molecule
Insoluble - Doesnt affect water potential
Branched/Helical - Makes molecule compact
Large molecule - Cannot cross cell membrane
More ends - Fast enzyme action
Structure of glycogen
Polymer of alpha glucose
Joined by glycosidic bonds
How does glycogen act as a source of energy
Hydrolysed to glucose
Glucose used in respiration
How is cellulose adapted to its function
Long and straight chains
Become linked together by many hydrogen bonds to form fibrils
Provide strength to cell wall
How to test for presence of a lipid in a sample of food
Add ethanol
THEN add water
AND shake
Milky/White emulsion
How is triglyceride molecule formed
ONE glycerol and THREE fatty acids
Condensation reactions AND removal of THREE molecules of water
Ester bonds formed
How is ester bond formed in phospholipid
Condensation reaction
Between glycerol and fatty acid
Describe the induced fit model
Substrate binds to the active site
Active site changes shape slightly so it is complementary to substrate
How do competitive inhibitors decrease the rate of enzyme controlled reactions
Inhibitor similar shape to substrate
Binds to active site
Reduces enzyme substrate complexes forming
How does the structure of a protein vary depending on the amino acids it contains
(5 Marks)
Structure is determined by position of amino acid
Primary structure is sequence of amino acids
Secondary structure formed by hydrogen bonding
