Immune System and Blood Platelets A.

Which of the following are concerned with the prevention of bacterial Infections In different parts of the human body? Alimentary canal Respiratory tract Blood A. Digestive enzymes hair white blood cells B. Mucus cilia red blood cells acid blood platelets D. Bile salts Directions: Questions 48 and 49 refer to the graph below which shows the changes In the concentration of antibodies In the blood of a person with time: 48. The increase in the antibody concentration on day 7 might be caused by A. Excessive bleeding B. The entry of bacteria C. Recovery from a disease D. The intake of a large amount of antibiotics 49. The antibody concentration increased rapidly on day 21 because the person A. Developed a fever. B. Received a vaccination. C. Was Infected by the same type of antigen. D. Produced a large number of phagocytes. 32. Which of the following components of the blood can destroy bacteria that have entered the body? (1) antibodies (2) phagocytes (3) blood platelets A. (1) and (2) o nly B. (1) and (3) only C. (2) and (3) onlyD. (2) and (3) 46. Which of the following are examples of artificial immunity? (1) Injection of vaccine into the body (2) Injection of antibodies into the body (3) Injection of antibiotics into the body A. (1) only B. (1) and (2) only 34. In the alimentary canal, bacteria in food are mainly killed by A. Saliva. B. Mucus. C. Gastric Juice D. Pancreatic Juice Directions: Questions 49 and 50 refer to the graphs below, which show the changes in the antibody level in the blood as a result of two methods of inducing immunity in humans: 49.Substance P can be (1) bacteria. (2) antigens. (3) antibodies. B. (3) only C. (1) and (2) only D. (2) and (3) only 50. What is the advantage of method 2 over method 1 in inducing immunity? A. The B. The immunity can develop faster. C. It can stimulate the white blood cells to produce more antibodies. D. The body can become immune against a wider range of diseases. 01 18. Which of the following statements about a ntibodies is correct? A. They act on specific antigens. B. They are produced by phagocytes. C. They develop a memory for antigensD. They can replicate rapidly during infection. 60. Which of the following structures produce secretions that can protect the body from infection? (1) skin (2) stomach (3) trachea 02 42. A person was infected by the same kind of pathogen twice within a month. Assuming the quantity of pathogen for both infections was the same, which of the following graphs correctly shows the change in the pathogen level in the person's blood?