ENZYMES
Student Name ______
1:
1)What term is used to describe a cellular reaction in which large molecules are broken down to smaller ones?______
2)What is metabolism? ______
3)Give an example of a catabolic reaction in an animal______
4)Give an example of an anabolic reaction in a plant______
5)Is energy release a feature of anabolic or catabolic reactions? ______
6)To which group of molecules do enzymes belong? ______
7)Name an enzyme and matching substrate ______
8)What is an enzyme? ______
9)Name an enzyme that is involved in the digestion of fat ______
10)True or false?-- Immobilised enzymes can act as catalysts ______
11)What is a bioreactor? ______
12)State one advantage of using an immobilised enzyme in a bioreactor. ______
______
13)What term best describes the shape of an enzyme? ______
14)Suggest a temperature at which human enzymes work best. ______
15)In the case of cold alcohol (ethanol) state the following:
(a) An investigation in which you used it ______
(b) The precise purpose for its use in the investigation that you have indicated ______
______
16)What is an amylase? ______
Name a site of amylase action. ______
What is the approximate pH value at this site? ______
17)What is meant by immobilisation? ______
18)Name a substance that is used to immobilise enzymes. ______
19)Give two advantages of using immobilised enzymes. ______
______
20)Give one application of a named immobilised enzyme. In your answer, refer to substrate, enzyme and product. ______
21)Is an enzyme a lipid, a protein or a carbohydrate? ______
22)Where in a cell are enzymes produced? ______
23)Name an enzyme that turns fats to fatty acids and glycerol. ______
24)What is meant by an enzyme’s optimum pH? ______
25)What is a denatured enzyme? ______
26)Answer the following in relation to a lipase:
(a) Where is it secreted? ______
(b) Where does it act? ______
(c) What is the approximate pH at its site of action? ______
27)Amylase is an enzyme that is found in saliva. State the substrate and the product of this enzyme.
______
28)(a) Name a carbohydrate-digesting enzyme in the human alimentary canal.______
(b) Where in the alimentary canal does this enzyme act? ______
(c) State the enzyme’s product(s). ______
2. Explain each of these terms:
1 Metabolism ______
2 Enzyme ______
3 Catalyst ______
4 Substrate ______
8 Optimum pH ______
9 Buffer tablet ______
21 Bioprocessing ______
24 *Specific ______
25 *Active site ______
26 *Denatured ______
27 *Induced fit theory ______
28 *Enzyme-substrate complex ______
6. Hydrogen peroxide is a liquid that slowly changes to water and oxygen gas over a number of weeks.
Catalase can speed up this reaction. We make catalase in our liver. A student used the apparatus
shown to investigate the effect of different temperatures on catalase action.
At each temperature, 2 cm3of hydrogen peroxide was dropped on to a 1 cm3cube of liver. The
volume of gas collected in two minutes at each temperature was measured. The results are shown
in the following table.
EMPERATURE (°C) 0 10 20 30 40 50 60
(a)Use the figures in the table to plot a graph of the results.
(b) (i) At which temperature is most oxygen produced?
______
Explain the likely reason. ______
______
(ii) What volume of oxygen would be produced at 25°C?
______
(iii) At what temperature would a volume of 80 cm3of
oxygen be produced? ______
(c) At 60°C no oxygen was produced. What would happen if this same cube of liver was cooled to
30°C and another 2 cm3of hydrogen peroxide was added? Explain your answer.
______
(d) Besides temperature, name another factor that might affect the rate of action of this enzyme.
______
17. Complete these sentences:
(a)Enzymes ______up the rate of chemical ______
(b)Enzymes are ______because they only work on one substrate.
(c)The substrate fits into the ______site on the surface of the ______
(d)With an increase in ______the rate of reaction ______
(e)But eventually a temperature is reached which ______the enzyme.
(f)Enzymes can be re-used, so only ______amounts are needed.