AQA A LEVEL BIOLOGY COMPREHENSIVE
EXAM STUDY GUIDE COMPLETE
QUESTIONS AND SOLUTIONS
●● What are monomers of carbohydrates called?
Answer: Monosaccharides.
●● Beta Glucose
Answer:
●● Alpha glucose
Answer:
●● Glucose formula
Answer: C₆H₁₂O₆
●● Name of the bond between monosaccharides?
Answer: Glycosidic bond.
●● What is sucrose made from?
Answer: Glucose and fructose.
,●● What is lactose made from?
Answer: Glucose and galactose.
●● What is maltose made from?
Answer: Two alpha glucose.
●● Testing for reducing sugars?
Answer: Add Benedict's reagent (blue) and heat in a water bath at a boil.
If present: Green → yellow → orange → brick red
●● Test for non-reducing sugars?
Answer: Add dilute hydrochloric acid and heat, neutralise with Sodium
Hydrogencarbonate and add Benedicts reagent.
●● What is the scientific name for carbohydrates?
Answer: Polysaccharides.
●● What is starch made of?
Answer: Starch is a mixture of two polysaccharides of alpha glucose:
Amylose and amylopectin.
●● What is amylose?
,Answer: A long, unbranched alpha glucose chain. The angles in it make
it have a coiled shape which makes it compact and effective for storage.
●● What is amylopectin?
Answer: A long, braqnched alpha glucose chain. The side branches mean
that enzymes can get to and hydrolise glycosidic bonds faster so glucose
can be released quickly.
●● What is glycogen?
Answer: A polysaccharide of alpha glucose with a similar structure to
starch except it is more branched, allowing even faster energy release. It
is also very compact.
●● What is celluose?
Answer: it is made of long. straight chains of beta glucose. The chains
are linked my hydrogen bonds to form microfibrils, a strong fibre. The
strong fibres allow it to provide structural support in cells as cell walls.
●● How to test for starch.
Answer: Add iodine which is dissolved in potassium iodie ti the sample.
Positive result: Turns blue-black. Negative result: stays browny-orange.
●● Which of proteins, polysaccharides and lipids are not a polymer.
Answer: Lipids.
, ●● What are triglycerides made of?
Answer: Glycerol and fatty acids.
●● What causes lipids to be insoluble in water?
Answer: The hydrophobic fatty acid tails.
●● What is the structure of a fatty acid?
Answer:
●● What do double bonds cause in fatty acids?
Answer: A kink in the chain.
●● Triglyceride formation?
Answer:
●● What are phospholipids?
Answer: Similar to triglycerides, but one of the fatty acid tails is
replaced by a phosphate group head.
●● Which part of a phospholipid is hydrophillic and which part is
hydrophobic?
EXAM STUDY GUIDE COMPLETE
QUESTIONS AND SOLUTIONS
●● What are monomers of carbohydrates called?
Answer: Monosaccharides.
●● Beta Glucose
Answer:
●● Alpha glucose
Answer:
●● Glucose formula
Answer: C₆H₁₂O₆
●● Name of the bond between monosaccharides?
Answer: Glycosidic bond.
●● What is sucrose made from?
Answer: Glucose and fructose.
,●● What is lactose made from?
Answer: Glucose and galactose.
●● What is maltose made from?
Answer: Two alpha glucose.
●● Testing for reducing sugars?
Answer: Add Benedict's reagent (blue) and heat in a water bath at a boil.
If present: Green → yellow → orange → brick red
●● Test for non-reducing sugars?
Answer: Add dilute hydrochloric acid and heat, neutralise with Sodium
Hydrogencarbonate and add Benedicts reagent.
●● What is the scientific name for carbohydrates?
Answer: Polysaccharides.
●● What is starch made of?
Answer: Starch is a mixture of two polysaccharides of alpha glucose:
Amylose and amylopectin.
●● What is amylose?
,Answer: A long, unbranched alpha glucose chain. The angles in it make
it have a coiled shape which makes it compact and effective for storage.
●● What is amylopectin?
Answer: A long, braqnched alpha glucose chain. The side branches mean
that enzymes can get to and hydrolise glycosidic bonds faster so glucose
can be released quickly.
●● What is glycogen?
Answer: A polysaccharide of alpha glucose with a similar structure to
starch except it is more branched, allowing even faster energy release. It
is also very compact.
●● What is celluose?
Answer: it is made of long. straight chains of beta glucose. The chains
are linked my hydrogen bonds to form microfibrils, a strong fibre. The
strong fibres allow it to provide structural support in cells as cell walls.
●● How to test for starch.
Answer: Add iodine which is dissolved in potassium iodie ti the sample.
Positive result: Turns blue-black. Negative result: stays browny-orange.
●● Which of proteins, polysaccharides and lipids are not a polymer.
Answer: Lipids.
, ●● What are triglycerides made of?
Answer: Glycerol and fatty acids.
●● What causes lipids to be insoluble in water?
Answer: The hydrophobic fatty acid tails.
●● What is the structure of a fatty acid?
Answer:
●● What do double bonds cause in fatty acids?
Answer: A kink in the chain.
●● Triglyceride formation?
Answer:
●● What are phospholipids?
Answer: Similar to triglycerides, but one of the fatty acid tails is
replaced by a phosphate group head.
●● Which part of a phospholipid is hydrophillic and which part is
hydrophobic?
