IGCSE Enzymes

What type of biological molecule is an enzyme?

• Lipid

• Carbohydrate

• Nucleic acid

• Protein

To which part of the enzyme does a substrate molecule bind?

Identify the temperature closest to the optimum temperature for a human enzyme

• 20℃

  
  

• 30℃

  
  

• 40℃

  
  

• 50℃

  
  

What term describes an enzyme because it speeds up a chemical reaction?

Where do most chemical reactions occur in a cell?

• Cytoplasm

• Ribosomes

• Nucleus

• Mitochondrion

Which organ of the body has enzymes with very low optimun pH

• Pancreas

• Small intestine

• Liver

• Stomach

Which structure in cells has enzymes to catalyse aerobic respiration?

• Nucleus

• Mitochondria

• Ribosomes

• Vacuoles

At temperatures that exceed the optimun an enzyme will become ---------

In an experiment to investigate the effect of temperature on the break down of hydrogen peroxide by catalase which of the following needs to be controlled?

• Temperature

• Concentration of enzyme

• Volume of oxygen produced

• Volme of carbon dioxide produced

Identify the optimum pH for an enzyme that catalyses the break down of starch in the mouth

• 2

• 5

• 7

• 9