Dec Revision Questions H2 2024 J1 ASRJC BIO

Anderson Serangoon Junior College Biology Department 1 JC1 H2 BIOLOGY December Revision Package 2024 JC1 H2 BIOLOGY DECEMBER REVISION PACKAGE NAME: ………………………………………………… CLASS: ………………………… Topic: CELLULAR STRUCTURES AND FUNCTION Question 1 [6 marks] TJC Prelims 2009 The electron micrograph in Fig. 1.1 shows an acinar cell found in the pancreas. Fig. 1.1 (a) With reference to Fig. 1.1, suggest the principal function of the pancreatic acinar cell. Give two reasons to explain your answer. [3]

Anderson Serangoon Junior College Biology Department 2 JC1 H2 BIOLOGY December Revision Package Fig. 1.2 shows two different structures, A and B, found in an animal cell. Fig. 1.2 (b) (i) Describe two ways in which A is similar to B. [2] (ii) The products of B are usually in the inactive form. Suggest the significance of this. [1] A B

Anderson Serangoon Junior College Biology Department 3 JC1 H2 BIOLOGY December Revision Package Topic: BIOMOLECULES AND CELL MEMBRANE Question 2 [11 marks] The figure below shows two molecules of glucose. (a) Draw the resulting maltose molecule arising from a dehydration reaction. [1] (b) Label the resulting bond. [1] Starch, a storage molecule in plants, is a polymer made of glucose molecules joined together. It consists of two components. (c) Name these two components. [2] (d) (i) Give one similarity between these two components. [1] (ii) Give two differences between these two components. [2] (f) The following figure shows a section of a cell surface membrane. (i) Explain why membranes are described as fluid mosaic in structure. [2] (ii) Some molecules are able to pass through the plasma membrane without the facilitation of transport proteins. Describe the unique properties of these molecules. [1] (iii) Outline two other roles of membrane proteins apart from their role in transport. [2]

Anderson Serangoon Junior College Biology Department 4 JC1 H2 BIOLOGY December Revision Package Topic: ENZYMES Question 3 [ 7 marks] JJC Prelims 2009 Meat is the muscle of an animal. When animals are slaughtered, biochemical changes occur in the muscles, resulting in the hardening of meat. There are several ways to make the meat tender again, and these usually involve the partial breaking down of the proteins that make up the muscle tissue. One way is to add the protein-digesting enzyme, papain, just before freezing the meat. As the meat is thawed and cooked, this enzyme digests the protein. (a) Suggest how the protein may be held in the active site of a papain while the reaction occurs. [2] (b) Use your knowledge of enzymes to explain: (i) Why the rate at which protein is digested increases as the meat warms up in the early stages of cooking. [2] (ii) Why protein digestion stops once the meat has be