Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
YOV WANT TO Sf A lEVKOt)lfE YOU'VE GOT TO ENGUlf .F($EIGN I ~ N~Ii\I\.t OODiE5 "Of' WHAfS 1JJE , LARRY r CHf.CXfN _ r ctass __ - Marks 1. The diagram shows the sequence of events as a white blood cell engulfs and destroys a bacterium. (a) Name the structures A, B and C. A B C (b) 2 (i) What is the name given to this process of engulfing the bacterium? 1 (ii) Describe the roles of structures Band C in the cell. B .... 1 C 1 (c) What does the lysosome contain? 1 write in this margin 1. (continued) Marks (.d) Another type of white blood cell could destroy this bacterium by producing antibodies. (i) Name this type of white blood cell. (1) (ii) What feature of the bacterium stimulates the production of antibodies? (1) (iii) Describe how the production of antibodies can be stimulated artificially. (1) WPJ1'EIN TfiIs 2. Marks The diagram below shows three stages in the humoral immune response. white blood cell foreign molecules nucleus () + y rough endoplasmic reticulum () o o () () stage 1 () o receptor stage 2 stage 3 plasma cell (i) (a) What type of white response? memory cell blood cell carries out the humoral immune 1 (ii) What name is given to foreign molecules which stimulate the immune response? 1 (b) Describe two responses made by the white blood cell as a result of the attachment of the foreign molecules. 1 2 MARGIN THIS MARGIN 2. Marks (continued) (c) Mature plasma cells contain a large quantity of rough endoplasmic reticulum. Explain this feature of these cells. 2 (d) Suggest the role of memory cells in the immune response. 1 (e) What term describes the secretion of substances, such as antibodies, out of a cell? 1 (fJ Describe how the body might obtain antibodies in a natural, passive way. 1 [Turn over DO NOT WRITE IN TillS M,\RGIN Marks 3. The diagram below shows blood from a person who has been infected by bacteria. These bacteria have triggered an immune response involving proteins P and Q. The diagram is not draum to scale. proteinQ~ T-Iymphocyte ~ .. @ bact"ia~ surface ~pmteinp o macrophage @... red ~ blood cell (a) (i) Identify proteins P and Q. (ii) 1 Q P Cell R produced protein Q. Name this type of cell. 1 (iii) Describe (A) the role of the following cells in combating infection. T'-Iymphocyte 1 (B) ~acrophage 1 DO NOT WRITE IN THIS MARGIN Marks 3. (continued) (b) Complete the following sentences by underlining one option from each pair of options shown in bold. (i) (ii) (c) Immunity gained after contracting a bacterial infection is an example of active I passive immunity that is naturally I artificially acquired. 1 Immunity gained from the injection of a tetanus vaccine is an example of active I passive immunity that is naturally I artificially acquired. 1 What happens during an autoimmune response? 1 [Turn over nl'\.l11 THI MARC 4. Marks The diagram below summarises different types' of immunity. A (a) B C D Complete the table using the letters A, B, C and D to match correctly each type of immunity with its description. Description of immunity Letter Ready-made antibodies are injected into the body. Babies get antibodies from breast mille Bacteria enter the body and stimulate the production of antibodies. Foreign antigens are injected into the body stimulate the production of antibodies. and 2 (b) The immune system sometimes over-reacts to a harmless substance. What term is used to describe this reaction? 1 (c) Rheumatoid arthritis is a condition in which the body attacks its own cells. What term is used to describe this type of condition? . 1 VVl<.11.t. 4. M47ks (continued) (d) After kidney transplant surgery, drugs are taken by the patient to reduce the normal immune response. Explain why this drug treatment is necessary. 2 (e) Some diseases are caused when cells in the body produce a harmful protein. Recent research has led to the development of antisense drugs to treat such diseases. These drugs carry a short strand of RNA nucleotides designed to attach to a small part of the mRNA molecule that codes for the harmful protein. (i) Suggest how these drugs may prevent the production protein. of a harmful 1 (ii) Antisense drugs can be used to treat autoimmune diseases. Describe what is meant by an autoimmune disease. 1 li" THIS MARGIN MARG 5. The diagrams below show a disease-causing virus and one of the same type which has been weakened to make it less harmfuL Disease-causing virus (a) Marks Weakened virus A woman is vaccinated with the weakened form of the virus. (i) Explain why she does not develop the disease from the vaccination. 1 (ii) What feature of the weakened VIruS results in her gaining immunity from the disease? 1 (iii) Explain why this form of immunity is described as being both artificial and active. Artificial _ 1 Active 1 (b) The table contains information about viruses. Tick (_t) the appropriate VIruses. boxes to show characteristics Characteristic which apply to all Tick (_t) Contains a nucleus Surrounded by a protein coat Can be seen under a light microscope - Contains nucleic acid Can only reproduce inside other cells 2 MARGIN 6. Marks The diagram shows a polio virus. 70nm (a) Viruses can only reproduce within a host cell. (i) List two substances, supplied by the host cell, which are required for viral replication .. 1 2 (ii) __ 1 What happens after the viruses have been assembled inside the cell? 1 (b) Viruses can be processed to make vaccines to protect against the disease. Suggest why it is important that the nucleic acid is damaged in the process, but not the protein coat. Nucleic acid damaged 1 Protein coat undamaged 1 (c) The average diameter of a red blood cell is 71lm. By how many times is a red blood cell bigger than a polio virus? (1 J.Lm = 1000 nm) Space for calculation 1 THI MARC 7. The diagram below represents the structure of the virus which causes influenza. (a) (i) Marks Name the substance which makes up the coat of this virus. 1 (ii) Describe how a virus from an influenza vaccine might differ in structure from the virus shown in the diagram. 1 (b) The following diagrams show a cell being attacked by the influenza virus. two days cell nucleus (i) Describe how the virus reproduces over the two day period. 2 (ii) State how viruses are released from the infected cell. 1 (c) There are three main types of influenza virus. Why are the antibodies produced others? against one type not effective against the 1 MARGIN 7. Marks (continued) (d) The deaths in Scotland caused by influenza, pneumonia between 1976 and 1982 are shown on the graph below. Key and bronchitis, actual deaths exgected deaths 1100 1000 900 800 Number of deaths 700 600 500 400 I 300 200 I 100 /' 1 January (i) 1976 1977 1978 1979 Year 1981 1982 What is the expected range of deaths in any year? __________________________ (ii) 1980 to __ 1 Suggest in which years influenza epidemics occurred in Scotland. 1 (iii) Chilling reduces the action of the cilia in the windpipe. Explain why this makes people more vulnerable winter. to influenza in the 1 (iv) Suggest why the actual deaths in 1980 did not have the same pattern as seen in other years. 4.1.J. ... \J MARGIN 8. Antigens on the surface of red blood cells enable different blood groups to be identified. Marks Four types of blood group are A, B, AB and O. The diagram shows antigens on a red blood cell and antibodies in the surrounding plasma. )- y -{ antibodies in plasma (a) t -t... Complete the table below to show the types of antigen and antibody present in individuals of each blood group. Blood group Antigens present on surface of red blood cells A A B Antibodies present in plasma anti-A AB 0 2 (b) Which blood group(s) could be transfused safely into a person of blood group A? 1 Wh.at you should know ...---------------, 5 (Chapters6-8) (See table 8.2 for word bank.) 1 The plasma surrounding a cell is composed of protein and phospholipid molecules. These are thought to be arranged as In the fluid ____ model. 6 Molecules or ions may enter or leave a cell by being transported across the membrane a concentration gradient from low to high concentration. This requires 2 The bilayer of molecules provides the cell with a stable boundary. The molecules vary in function. Some give support, some contain ____ allowing' passive transport of small molecules, others act as and actively transport molecules into or out of the cell. 7 Endocytosis is the process by which the cell membrane relatively large particles in a vesicle. is the process by which a vesicle formed in the cell fuses with the membrane and expels its contents to the exterior. 3 The membranes surrounding cell have the same basic structure as the plasma membrane. 8 Immunity to disease-causing organisms can be innate or acquired. immunity is inborn; ____ immunity is gained during the person's lifetime. 4 A constant environment is maintained within a cell by the membrane acting as a barrier and regulating the entry and of materials. I What you should know I = ~c::::e::a~e~~uni~ 9 by which cells such as engulf bacteria and destroy them using enzymes in _ is 10 Antibody production is a type of acquired immunity. It is the response made by cells called to the presence in the body of alien molecules called ____ . An possesses receptor sites which bind to one particular type of antigen and render it harmless. B-lymphocytes produce free ( ) antibodies to deal with antigens; T-lymphocytes employ direct contact ( response) to destroy cells infected with antigens. 12 Natural is acquired by a person who suffers and survives a disease by producing appropriate antibodies. Some B- and T-lymphocytes remain as . ____ cells. immunity is acquired by a person who receives a harmless form of the antigen and responds by producing T and B cells and antibodies. 13 Active immunity is gained by a person's _ system responding to an antigen and producing it's own antibodies; immunity is gained by a person receiving antibodies made by another person or animal. 14 An over-reaction to a harmless substance by the immune system is called an reaction. 15 Each person's cells have an antigen _ which is recognised by the immune system as 'self'. This normally guarantees the cells' safety. However under exceptional circumstances, occurs and the immune system attacks 'self' cells. Small molecules may enter or leave the cell by moving passively by (or osmosis) along a concentration from high to low concentration. Continued :> 16 Viruses are very tiny micro-organisms which are unusual in that is the only true characteristic of living things that they exhibit. 17 A virus consists of DNA or surrounded by a coat of protein. It depends on the host cell for energy and building materials. 18 Once inside the host cell, a virus alters the cell's biochemistry, enabling mass of viral nucleic acid to occur. Many copies of the virus are produced and released by of the host cell. 19 Some viral diseases can be prevented using vaccines containing virus to induce immunity. 20 Human Immunodeficiency Virus disrupts the immune system by slowly destroying T cells. Attempts to produce a vaccine have so far failed. WYSK6 - 8 Topic 6 Immunity acquired engulfs actively exit against exocytosis allergic gradient antibody helper antigens humoral artificial Immune attenuated immunity autoimmunity innate carriers lymphocytes cell-mediated lysis _ channels lysosomes. diffusion macrophages energy membrane memory mosaic organelles passive phagocytosis phospholipid protein replication reproduction RNA selective signature Essay Questions 1. Give an account oUhe response of the body's immune system following viral invasion (10) Maximum 8 marks 1 mark coherence 1 mark relevance 2. Give an account o(immunitv under the following headings: (i) Bvlymphocytes and T -lymphocytes; (7) (ii) Macrophages (3) (10) 3. Discuss the humoral immune system under the following headings: (i) Naturally acquired active immunity (6) (ii) Naturally acquired passive active immunity (2) (iii) Autoimmunity (2) (10) 4. Give an account o(immunisation under the following headings: (i) Artificial active immunity (6) (ii) Artificial passive immunity (2) (iii) The impact of vaccination on childhood diseases (2) (10)