1) Biological Molecules Flashcards
What is the basic unit of starch?
Alpha glucose
What is the basic unit of glycogen?
Alpha glucose
What is the basic unit of cellulose?
Beta glucose
What is the structure of starch? (3 points)
- 30% amylose (a spiral with 1,4 bonds)
- 70% amylopectin (has branches with 1,4 and some 1,6 bonds)
- combined to give appearance of tightly wound molecule
What is the structure of glycogen? (3 points)
- has 1,4 and 1,6 bonds
- similar structure to amylopectin, however is further branched
- branched structure
What is the structure of cellulose? (2 points)
- has 1,4 bonds
- straight chains of beta glucose units
What is the function of starch?
Main storage molecule in plants
What is the function of glycogen?
Main storage carbohydrate in mammals
What is the function of cellulose?
Gives plant cell walls their structural strength
How does the structure of starch aid the function? (3 points)
- must be quite big so it isn’t soluble; this prevents an osmotic effect
- must be compact to hold its content
- can be easily hydrolysed to soluble sugars
How does the structure of glycogen aid the function?
It needs to meet the superior energy demand of animals, so the long branched structure enables a quicker build up and break down of glycogen
How does the structure of cellulose aid the function?
Given their strength as they are made of microfibrils
How are microfibrils made? (cellulose)
When hydrogen bonds form as the straight beta glucose chains are laid next to each other, strengthening them into larger sub units
What is a condensation reaction?
Joins 2 or more monosaccharides
What is released in a condensation reaction?
Water
What bond is formed in a condensation reaction?
Glycocidic
What is a hydrolysis reaction?
Separating of polysaccharides into disaccharides or monosaccharides
What does hydrolysis USE?
Water
What are energy sources for cells?
Monosaccharides and disaccharides
What are monosaccharides and disaccharides energy sources for?
Cells
What is the simplest carbohydrate?
Monosaccharide
How many sugar molecules in a monosaccharide?
1
What monosaccharides are reducing sugars?
- glucose
- fructose
- galactose
What does the condensation of 2 monosaccharides form?
Disaccharide
What does the combination of 2 glucose monosaccharides form?
Maltose
What makes up maltose?
Glucose + Glucose
What does the combination of glucose and fructose monosaccharides form?
Sucrose
What does the combination of glucose and galactose monosaccharides form?
Lactose
What makes up sucrose?
Glucose + Fructose
What makes up Lactose?
Glucose + Galactose
What disaccharides are reducing sugars?
- maltose
- lactose
What disaccharide is a non-reducing sugar?
Sucrose
What is polysaccharide?
Long polymers; many monosaccharides and disaccharides combined
What are examples of polysaccharides?
- starch
- glycogen
- cellulose
What test can be used for reducing sugars?
Benedicts solution test
What test can be used for starch?
Iodine in potassium iodide
How do you carry out the benedicts test for reducing sugars?
Heat the benedicts solution with the sugar at least at 73degreesC
What shows a positive result for reducing sugars in the benedicts test?
The solution will turn from blue to dark red
How do you carry out the iodine in potassium iodide test for starch?
Mix it with the reducing sugars
What shows a positive result for starch in the iodine test?
It will turn from orange to blue/black