State the chemical composition of a glucose molecule.
- or CHO in ratio 1:2:1
1 mark
Alternative Method
- Carbon, hydrogen and oxygen
1 mark
Describe the role of glucagon in promoting the breakdown of glycogen during fasting.
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Fasting reduces blood glucose which stimulates the release of glucagon
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Glucagon is a hormone released by the pancreas when blood sugar levels are low
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Glucagon increases the blood glucose level when it falls below normal levels
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Glucagon accelerates the conversion of glycogen in the liver into glucose/promotes glycogenolysis
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Glucagon promotes glucose formation from amino acids
1
Explain the advantages of the ATP-CP system in regenerating ATP during a 50-meter sprint.
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ATP-CP system allows ADP to gain phosphate molecule almost instantaneously, enabling quick recovery
1 mark -
Does not require oxygen (anaerobic)
1 mark -
CP is readily available within skeletal muscle
1 mark -
Provides energy for explosive high intensity exercise/movement
1 mark -
No fatiguing by-products produced
1 mark
Describe how glucose units join together to create disaccharides and polysaccharides.
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Glucose units join through condensation reaction/dehydration synthesis with loss of water
1 mark -
Glycosidic bond forms between two -OH groups, creating an -O- bridge between monosaccharide units
1 mark
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Each polysaccharide contains many (tens/hundreds) of monosaccharides joined through dehydration synthesis
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Glycosidic bond provides the backbone structure for larger carbohydrate molecules
