Human Health and Disease (SKCH PU College) PDF

HUMAN HEALTH AND DISEASE DEPARTMENT OF BIOLOGY SKCH PU COLLEGE  HUMAN HEALTH AND DISEASES  Health is a state of complete physical, mental and social wellbeing.  Health is affected by genetic disorders, infections, change in lifestyle (food, water, rest exercise etc).  W...

HUMAN HEALTH AND DISEASE DEPARTMENT OF BIOLOGY SKCH PU COLLEGE  HUMAN HEALTH AND DISEASES  Health is a state of complete physical, mental and social wellbeing.  Health is affected by genetic disorders, infections, change in lifestyle (food, water, rest exercise etc).  When the functioning of organs or systems of the body is affected, it is called a disease.  Diseases may be infectious (transmits from one person to another ex AIDS) or non-infectious (do not transmit ex cancer).  Disease causing organisms are called pathogens. Parasites are pathogens are they harm the host.  Good humour hypothesis (by Hippocrates & Indian ayurveda system): it states that health is a state of body & mind where there is a balance of certain humours. Person with ‘black bile’ belong to hot personality and would have fevers.  William Harvey disproved this hypothesis. He discovered blood circulation and demonstrated normal body temperature in persons with black bile using thermometer. COMMON INFECTIOUS DISEASES IN MAN: BACTERIAL DISEASES: DISEASE PATHOGEN MODE OF COMMON TRANSMISSION SYMPTOMS 1.Typhoid Salmonella typhi It enters small intestine Sustained high fever ( through food & water and 390_ 400c), headache, migrates to other organs via weakness, stomach pain blood , constipation & loss of appetite, intestinal perforation and death may occur.  Widal test is used for confirmation of the disease.  Mary Mallon (typhoid mary) was a professional cook. She was a typhoid carrier who spread typhoid for several years through the food she prepared. DISEASE PATHOGEN MODE OF SYMPTOMS TRANSMISSION 1.Ascariasis Ascaris lumbricoides. The eggs of the parasite are A healthy person (round worm) excreted along with the acquires this infection endoparasite of small faeces of infected persons through contaminated intestine. which contaminate  2.Pneumonia Streptococcus Inhaling the droplets Respiratory problems, pneumonia & /aerosols released by an fever, chills, cough, Haemophilus infected person. Sharing headache. In severe case, influenzae. glasses and utensils with an lips and finger nails turn It infect lung alveoli. infected person. grey to bluish color. The alveoli get filled with fluid leading to respiratory problems. Other bacterial diseases: Dysentery- is caused by shigella bacteria. Plague- is caused by yersinia pestis by rodents, fleas. Diphtheria - is caused by Corynebacterium diphtheriae VIRAL DISEASES: DISEASE PATHOGEN MODE OF SYMPTOMS TRANSMISSION 1.Common Rhinoviruses Inhaling droplets resulting Nasal congestion & cold from cough or sneezes. discharge, fever, Through contaminated headache, sore throat, objects (pens, books, cough, hoarseness, cups,doorknobs,computer tiredness etc. accessories ) etc. Common cold lasts for 3-7 days. HELMINTH DISEASES: DISEASE PATHOGEN MODE OF SYMPTOMS TRANSMISSION Ascariasis Ascaris lumbricoides Soil , water ,vegetables, Internal bleeding, fruits etc. contaminated with muscular pain, fever, faeces containing eggs of anemia & blockage of paraisites. the intestinal passage. 2.Filariasis Filarial worms or Bite of female culex Chronic inflammation of (Elephantiasis) Wuchereria bancrofti & mosquito. organs in which they live w. malayi. for many years , usually the lymphatic vessels of the lower limbs and the disease is called elephantiasis or filariasis. The genital organs are also affected , resulting in gross deformities. Fungal disease DISEASE PATHOGEN MODE OF SYMPTOMS TRANSMISSION Fungal disease Ringworm pathogens From soil or by using Appearance of dry are Microsporum, towels, clothes or comb of ,scaly lesions on various Trichophyton, & infected person. parts of the body such Epidermophyton. as skin ,nails and scalp. these lesions are accompanied by intense itching. heat and moisture help these fungi to grow , which makes them thrive in skin folds such as those in the groin or between the toes. PROTOZOAN DISEASE: DISEASE PATHOGEN MODE OF SYMPTOMS TRANSMISSION 1.Amoebiasis Entamoeba histolytica Houseflies act as mechanical Constipation, abdominal (amoebic carriers and serve to transmit pain & Cramps, stools dysentery) the parasite from faeces of with excess mucus and infected person to food and blood clots. food products. Drinking water and food contaminated by the faecal matter are the main source of infection. Malaria is caused by digenetic protozoan parasite called plasmodium. Life cycle of plasmodium requires two hosts: human & mosquitoes for completion Note- Types of malaria: 1. Benign tertian malaria caused by Plasmodium vivax. 2. Quartan malaria caused by Plasmodium malariae. 3. Malignant tertian malaria caused by Plasmodium falciparum. 4. Mild tertian malaria caused by Plasmodium ovale. LIFE CYCLE OF PLASMODIUM:  Plasmodium enters the human body as sporozoites (infective stage) through the bite of an infected female anopheles mosquito( vector).  The sporozoites reach the liver cells via blood where the initially multiply asexually. These then attack the RBCs resulting in their rupturing.  The rupture of RBCs is associated with the release of haemozoin, a toxin which causes the chill and high recurring fever every three to four days.  The female anopheles mosquito when bites an infected human being, the malarial parasites enter into the mosquito’s body and undergo further development to form sporozoites that finally move to the salivary glands of the insect.  The bite of these mosquitoes introduces the sporozoites inside the human body, thus initiating the above mentioned cyclic process again. Symptoms: Tiredness, headache and muscular pain.  Malaria is characterized by recurring rigors lasting 6-10 hours.  There are three stages:  (i) Cold stage( chill and shivering ) (ii)Hot stage (temperature rise) (iii)Sweating stage (perspiration and gradual fall in temperature).  Prevention and control of disease: The important measures to control malaria include controlling or eliminating the vectors and their breeding places which can be achieved by fitting doors and windows with wire nets , using repellents etc, avoiding stagnation of water in and around residential areas , regular cleaning of household coolers , use of mosquito nets,  introducing fishes like Gambusia in ponds that feed on mosquito larvae, spraying of insecticides in ditches , drainage areas and swamps, etc.  Personal hygiene: keep the body clean, use clean drinking water, food etc.  Public hygiene: proper disposal of wastes and excreta.  Periodic cleaning and disinfection of water reservoirs, pools, tanks.  Avoid contact with infected persons or their belongings (to control air –borne diseases).  Precautions can avoid vector borne disease like  Malaria – Plasmodium vivax Filariasis - Culex mosquito Dengue & Chikungunya - Aedes mosquitoes.  Vaccines & immunization helped to control diseases like small pox, polio, diphtheria, pneumonia & tetanus.  Drugs like antibiotics also helped to treat infectious diseases. IMMUNITY: The ability of the host to fight the disease causing organisms, conferred by immune system is called immunity.  Immunity is of two types: (i) Innate immunity (ii) Acquired immunity.  Innate immunity: It is non-specific type of defence , that is present at the time of birth. This is accomplished by providing different types of barriers to the entry of the foreign agents into our body.  Innate immunity consists of four types of barriers. 1. Physical barriers: Skin on our body is main barrier which prevents entry of the microorganisms. Mucus coating of the epithelium lining the respiratory, gastrointestinal and urogenital tracts also help in trapping microbes entering our body. 2. Physiological barriers: Acid in the stomach, saliva in the mouth, tears from eyes all prevent microbial growth. 3. Cellular barriers: Certain types of leucocytes (WBC) of our body like polymorpho- nuclear leucocytes (PMNL- neutrophils) and monocytes and natural killer ( type of lymphocytes ) in the blood as well as macrophages in tissues can phagocytose and destroy microbes. 4. Cytokine barriers: Virus infected cells secrete proteins called interferons which protect non infected cells from further viral infection Acquired immunity :  Acquired immunity, on the other hand is pathogen specific. It is characterised by memory. This means when our body encounters a pathogen for the first time it produces a response called primary response which is of low intensity.  Subsequent encounter by same pathogen produce highly intensified response called secondary response or anamnestic response due to memory of first  encounter.  Primary and secondary responses are carried out with the help of B- lymphocytes and T lymphocytes.  B-lymphocytes produce army of protein in response to pathogens into our blood to fight with them.  T lymphocytes : help B cells to produce antibodies. These proteins are called antibodies.  each antibody molecule has four polypeptide chains, two small called light chains and two longer heavy chains  Both are arranged in the shape of ‘Y’, hence an antibody is represented as (H2L2). Different types of antibodies are produced in our body – IgA, IgM, IgE, IgG are some them. Types of acquired immune response:  Humoral immune response / antibody mediated immunity (AMI): These antibodies are found in the blood, the response is also called as humoral immune response. This is one of the two types of our acquired immune response – antibody mediated.  Cell mediated response / cell mediated immunity (CMI): It is the immune response mediated by T lymphocytes (T cells) the body can differentiate ‘self ‘and ‘non self ‘ and the CMI causes graft rejection.  Active and passive immunity: On the basis of production of antibodies, immunity can be further categorized as – 1. Active immunity: When a host is exposed to antigens, which may be in the form of living or dead microbes or other proteins, antibodies are produced in the host body. This type of immunity is called active immunity. 2. Active immunity is slow and takes time to give its full effective response. Injecting the microbes deliberately during immunisation or infectious organisms gaining access into body  during natural infection induce active immunity. 3. Passive immunity: Readymade antibodies are directly given to protect the body against foreign agents.  The yellowish fluid colostrum secreted by mother during the initial days of lactation has abundant antibodies IgA to protect the infant.The foetus also receives some antibodies from their mother through the placenta during pregnancy. This is an example of passive immunity provided by the mother to her child. Vaccination and Immunisation :  The principle of immunisation or vaccination is based on the property of memory of the immune system.  1. Active immunization : In this, preparation of vaccine ( antigenic proteins of pathogen or inactivated pathogen) is introduced in the body. it results in development of antibodies.  During infection , the antibodies neutralize antigens.  The vaccines also generate memory B & T cells. They recognize the pathogen quickly. Ex polio vaccine, hepatitis B vaccine , DPT vaccine etc.  Vaccines are produced using DNA recombinant technology. Ex hepatitis B produced from yeast. 2. Passive immunization : It is the direct injection of pre-formed antibodies or antitoxin. It is required for quick immune response. Ex immunization against Tetanus, snake venom etc. Allergies: It is the exaggerated response of the immune system to certain antigens present in the environment.  Allergens: The substances to which immune system response is produced are called allergens.  Antibodies produced against the allergens are IgE type.  Common examples of allergens are mites in dust, pollens, animal dander etc.  Symptoms of allergic reactions are sneezing, watery eyes , running nose & difficulty in breathing, wheezing ,skin rashes.  IgE binds on mast cells to release chemicals like histamine and serotonin from them.it results in allergic reactions.  The use drugs like anti- histamine, adrenaline and steroids reduce the symptoms of allergy.  Asthma is a respiratory disease due to allergy. Auto immunity:  Memory based acquired immunity evolved in higher vertebrates based on the ability to differentiate foreign organisms. ex pathogens from self cells.  Sometimes, due to genetic and other unknown reasons , the body attacks self cells. This results in damage to the body is called auto immune disease.  Ex Rheumatoid arthritis. Immune system in body:  The human immune system consists of lymphoid organs, tissues, cells and soluble molecules like antibodies.   Immune system is unique in the sense that it recognizes foreign antigens, responds to these and remembers them.  The immune system, also plays an important role in allergic reactions, auto immune diseases and organ transplantation.  Lymphoid organs: These are the organs where origin and / or maturation and proliferation of lymphocytes occur. Two types of lymphoid organs are 1. Primary lymphoid organs are bone marrow and thymus where immature lymphocytes differentiate into antigen sensitive lymphocytes. After maturation the lymphocytes migrate to secondary lymphoid organs like spleen, lymph nodes, tonsils, peyer are patches of small intestine and appendix. 2. Secondary lymphoid organs provide the sites for interaction of lymphocytes with the antigen, which then proliferate to become effector cells. 3. Bone marrow is the main lymphoid organ where all the blood cells including B &T lymphocytes are produced. 4. Thymus is a lobed organ located near the heart and beneath the breastbone. The thymus is quite large at the time of birth but keeps reducing in size with age and by the time puberty is attained it reduces to very small size. Both bone marrow and thymus provide environment for the development and maturation of T lymphocytes. 5. Spleen is a large bean shaped organ. It mainly consists of lymphocytes and phagocytes. It acts as a filter of the blood by trapping blood borne microorganisms. Spleen also has a large reservoir of erythrocytes in foetus. 6. Lymph nodes are small solid structures located at lymphatic system.They trap microorganisms or other antigens. Trapped antigens activate lymphocytes and cause immune response. 7. There is lymphoid tissue also located within the lining of the major tracts (respiratory, digestive and urogenital tracts) are called mucosa associated lymphoid tissue (MALT). It constitutes about 50% of the lymphoid tissue in human body. AIDS: (Acquired Immuno Deficiency Syndrome)  It is deficiency of immune system.  Syndrome means a group of symptoms.  It is caused by HIV (Human immunodeficiency virus), a retrovirus having RNA genome.  AIDS was first reported in America (1981). In the last 25 years  Transmission of HIV infection – a. Sexual contact with infected person. b. By transfusion of contaminated blood and blood products. c. By sharing infected needles as in the case of intravenous drug abusers. d. From infected mother to her child through placenta.  HIV does not spread by touch or physical contact. It spreads only through body fluids.  There is always a time lag between the infection and appearance of AIDS symptoms. This period may vary from a few months to many years (5-10 years). Replication of retrovirus:  Once the virus gets into the body of the person, the virus enters into macrophages where RNA genome of the virus replicates to form viral DNA with the help of the enzyme reverse transcriptase.  This viral DNA gets incorporated into host cell’s DNA and directs the infected cells to produce virus particles.  The macrophages continue to produce virus and in this way acts like a HIV factory.  The progeny viruses released in the blood attack other helper T-lymphocytes. This is repeated leading to a progressive decrease in the number of helper T – lymphocytes in the body of the infected person.  During this period, the person suffers from bouts of fever , diarrhea and weight loss. Due to decrease in the number of helper T- lymphocytes, the person starts suffering from infections that could have been otherwise overcome such as those due to bacteria especially mycobacterium ,viruses, fungi and even parasites like Toxoplasma.  A widely used diagnostic test for AIDS is enzyme linked immune sorbent assay(ELISA). STreatment of AIDS with anti retroviral drugs is partially effective. Prevention of AIDS:  Educate people about AIDS through organizations like National AIDS Control Organization (NACO), nongovernmental organizations (NGOs), WHO etc.  Making blood (from blood banks) safe from HIV,  Ensuring the use of only disposable needles and syringes in public and private hospitals and clinics,  Advocate safe sex and free distribution of condoms.  Controlling drug abuse,  Promoting regular check-ups for HIV in susceptible populations Cancer:  Cancer is an abnormal and uncontrolled multiplication of cells resulting in the formation of tumor (masses of cell).  Normal cells show a property called contact inhibition by virtue of which contact with other cells inhibits their uncontrolled growth. Cancer cells appears to have lost this property.  As a result of this, cancerous cells just continue to divide giving rise to masses of cells called tumors.  Tumors are of two types: benign and malignant.  Benign tumors normally remain confined to their original location and do not spread to other parts of the body and cause little damage.  The malignant tumors, on the other hand are a mass of proliferating cells called neoplastic or tumor cells. These cells grow very rapidly, invading and damaging the surrounding normal tissues.  Cells sloughed from such tumors reach distant sites through blood, and wherever they get lodged in the body, they start a new tumor there. This property called metastasis is the most feared property of malignant tumors. Causes of cancer :  Transformation of normal cells into cancerous neoplastic cells may be induced by physical, chemical or biological agents. These agents are called carcinogens.  Ionising radiations like X-rays and gamma rays and non-ionizing radiations like UV cause DNA damage leading to neoplastic transformation.  The chemical carcinogens present in tobacco smoke have been identified as a major cause of lung cancer.  Cancer causing viruses called oncogenic viruses have genes called viral oncogenes. Furthermore, several genes called cellular oncogenes (c-onc) or proto oncogenes have been identified in normal cells which, when activated under certain conditions, could lead to oncogenic transformation of the cells. Cancer detection and diagnosis :  Cancer detection is based on biopsy and histopathological studies of the tissue and blood and bone marrow tests for increased cell counts in the case of leukemias.  In biopsy, a piece of the suspected tissue cut into thin sections is stained and examined under microscope (histopathological studies) by a pathologist.  Techniques like radiography (use of X-rays), CT (computed tomography) and MRI (magnetic resonance imaging) are very useful to detect cancers of the internal organs.  Computed tomography uses X-rays to generate a three-dimensional image of the internals of an object.  MRI uses strong magnetic fields and non-ionizing radiations to accurately detect pathological and physiological changes in the living tissue.  Antibodies against cancer -specific antigens are also used for detection of certain cancers.  Molecular biology technique: to detect cancer related genes. Such individual should avoid carcinogens ex tobacco smoke.  Treatment of cancer:  The common approaches for treatment of cancer are surgery, radiation therapy and immunotherapy.  In radiotherapy, tumor cells are irradiated lethally, taking proper care of the normal tissues surrounding the tumor mass.  Chemotherapeutic drugs are used to kill cancerous cells. Some of these are specific for particular tumors. Majority of drugs have side effects like hair loss, anemia, etc.  Tumor cells have been shown to avoid detection and destruction by immune system. Therefore, the patients are given substances called biological response modifiers such as α-interferon which activates their immune system and helps in destroying the tumor.  Surgery: most cancers are treated by combination of surgery, radiotherapy and chemotherapy. Drugs and Alcohol Abuse:  The drugs, which are commonly abused are opioids, cannabinoids and coca alkaloids. Majority of these are obtained from flowering plants. Some are obtained from fungi.  Opioids are the drugs, which bind to specific opioid receptors present in our central nervous system and gastrointestinal tract.  Heroin commonly called smack is chemically diacetylmorphine which is a white, odourless, bitter crystalline compound. This is obtained by acetylation of morphine which is extracted from the latex of poppy plant Papaver somniferum.  Generally taken by snorting and injection, heroin is a depressant and slows down body functions.  Cannabinoids are a group of chemicals which interact with cannabinoid receptors present principally in the brain. Natural cannabinoids are obtained from the inflorescences of the plant Cannabis sativa. The flower tops, leaves and the resin of cannabis plant are used in various combinations to produce marijuana, hashish, charas and ganja. It is taken by inhalation and oral ingestion, these are known for their effects on cardiovascular system of the body.  Coca alkaloid or cocaine is obtained from coca plant Erythroxylum coca. It interferes with the transport of the neuro-transmitter dopamine. Cocaine, commonly called coke or crack is usually snorted. It has a potent stimulating action on central nervous system, producing a sense of euphoria and increased energy. Excessive dosage of cocaine causes hallucinations.  Other well-known plants with hallucinogenic properties are Atropa belladona and Datura.  Cannabinoids are also being abused by some sportspersons.  Drugs like barbiturates, amphetamines, benzodiazepines, and other similar drugs, that are normally used as medicines to help patients cope with mental illnesses like depression and insomnia, are often abused.  Morphine is a very effective sedative and painkiller, and is very useful in patients who have undergone surgery.  Several plants, fruits and seeds having hallucinogenic properties have been used for hundreds of years in folk-medicine, religious ceremonies and rituals all over the globe. When these are taken for a purpose other than medicinal use or in amounts/frequency that impairs one’s physical, physiological or psychological functions, it constitutes drug abuse. Smoking:  Tobacco has been used by human beings for more than 400 years. It is smoked, chewed or used  as a snuff. Tobacco contains a large number of chemical substances including nicotine, an alkaloid. Nicotine stimulates adrenal gland to release adrenaline and nor- adrenaline into blood circulation, both of which raise blood pressure and increase heart rate.  Smoking is associated with increased incidence of cancers of lung, urinary bladder and throat, bronchitis, emphysema, coronary heart disease, gastric ulcer, etc.  Tobacco chewing is associated with increased risk of cancer of the oral cavity.  Smoking increases carbon monoxide (CO) content in blood and reduces the concentration of oxyhaemoglobin. This causes oxygen deficiency in the body. Adolescence & Drug / Alcohol Abuse:  Adolescence means both ‘a period’ and ‘a process’ during which a child becomes mature in terms of his/her attitudes and beliefs for effective participation in society.  The period between 12-18 years of age may be thought of as adolescence period.  Adolescence is a bridge linking childhood and adulthood. Adolescence is accompanied by several biological and behavioral changes. It is a very vulnerable phase of mental and psychological development of an individual. Causes of drug /alcohol use in adolescence:  Need for adventure and excitement, and experimentation.  curiosity or experimentation,  To escape facing problems.  Stress, from pressures to excel in academics or examinations.  Television, movies, newspapers, internet etc.  unstable or unsupportive family structures and peer pressure. Addiction and Dependence:  Addiction is a psychological attachment to certain effects –such as euphoria and a temporary feeling of well-being – associated with drugs and alcohol. With repeated use of drugs, the tolerance level of the receptors present in our body increases.Thus receptors respond only to higher doses of drugs or alcohol leading to greater intake and addiction.  Dependence is the tendency of the body to manifest a characteristic and unpleasant withdrawal syndrome if regular dose of drugs/alcohol is abruptly discontinued. This is characterised by anxiety, shakiness, and nausea and sweating, which may be relieved when use is resumed again.  Dependence leads to social adjustment problems. Effects of drug / alcohol abuse:  Reckless behaviour, vandalism and violence.  Excessive doses of drugs may lead to coma and death due to respiratory failure, heart failure or cerebral hemorrhage.  Drugs mixed with alcohol may cause death.  Damage of nervous system and liver cirrhosis.  Mental and social distress to family and friends.  Social problems like stealing and spread of infectious diseases (e.g. AIDS, hepatitis B).  Use of drugs and alcohol by pregnant woman affect the fetus (foetal alcohol syndrome or FAS)  Loss of sexual drive and nercospermia.  Misuse of drugs by athletes (eg.narcotic, analgesics, anabolic steroids, diuretics & certain hormones to increase muscle strength and bulk and to promote aggressiveness). Warning signs of drug/ alcohol abuse in adolescence period:  Drop in academic performance and absence from school.  Lack of interest in personal hygiene.  Withdrawal and isolation.  Depression, fatigue, aggressive and rebellious behavior.  Change in sleeping and eating habits  Fluctuations in weight , appetite etc  Loss of interest in hobbies.  Deteriorating relationships with family and friends. Side effects of anabolic steroid abuse: In males :  Acne  Mood swings and depression.  Increased aggressiveness.  Reduced testicles.  Decreased sperm.  Breast enlargement.  Kidney and liver dysfunction.  Premature baldness.  Enlargement of prostate gland. In females:  Masculinisation  Mood swings and depression.  Increased aggressiveness.  Excessive hair growth.  Abnormal menstrual cycle.  Deepening of voce  Enlargement of clitoris.  In adolescent male and female: severe facial and body acne, premature closure of the growth centres of the long bones resulting in stunted growth Prevention and control: Some of the measures useful for prevention and control of alcohol and drugs abuse among adolescents  Avoid undue peer pressure - Every child has his/her own choice and personality, which should  be respected and nurtured. A child should not be pushed unduly to perform beyond his/her threshold limits; be it studies, sports or other activities.  Education and counseling - Educating and counseling him/ her to face problems and stresses, and to accept disappointments and failures as a part of life. It would also be worthwhile to channelise the child’s energy into healthy pursuits like sports, reading, music, yoga and other extracurricular activities.  Seeking help from parents and peers - Help from parents and peers should be sought immediately so that they can guide appropriately. Help may even be sought from close and trusted friends. Besides getting proper advise to sort out their problems, this would help young to vent their feelings of anxiety and guilt.  Looking for danger signs - Alert parents and teachers need to look for and identify the danger signs discussed above. Even friends, if they find someone using drugs or alcohol, should not hesitate to bring this to the notice of parents or teacher in the best interests of the person concerned. Appropriate measures would then be required to diagnose the malady and the underlying causes. This would help in initiating proper remedial steps or treatment.  Seeking professional and medical help - A lot of help is available in the form of highly qualified psychologists, psychiatrists, and deaddiction and rehabilitation programmes to help individuals who have unfortunately got in the quagmire of drug/alcohol abuse. With such help, the affected individual with sufficient efforts and will power, can get rid of the problem completely and lead a perfectly normal and healthy life. MULTIPLE CHOICE QUESTION 1. Discovery of blood circulation by William Harvey disproved A. Good Humor hypothesis B. Germ theory of disease C. Ayurveda system D. None of these 2. Select the false statement A. Widal test is used for confirmation of typhoid B. Malaria is transmitted through Culex mosquito C. Mary Mallon (Typhoid Mary) was a typhoid carrier who continued to spread typhoid for several years. D. Plasmodium releases haemozoin E. Cocaine + antidepressants causes hypertension AAM@SSC 3. Of the following statements, related to Pneumonia, pick out the wrong statement. A. In this, the lung alveoli get filled with fluid leading to severe problems in respiration B. In severe cases, the lips and finger nails may turn gray to bluish in colour C. It is caused by 2 protozoans, Streptococcus pneumoniae and Haemophilus influenzae D. It is transmitted by inhaling droplets from an infected person or sharing utensils with an infected person 4. Analyze the statements concerned with common cold a. A group of Rhino viruses cause common cold b. They infect the nose, respiratory passage and lungs. c. It is characterized by nasal congestion & discharge,sore throat, hoarseness, cough, headache, tiredness, etc. d. Droplets from an infected person are inhaled directly or transmitted through contaminated objects such as pens, books, cups, doorknobs, computer keyboard, mouse etc. Of these statements, A. b & d are wrong B. Only b is wrong C. a & d are wrong D. Only d is wrong 5. Most serious malaria (malignant malaria) is caused by A. Plasmodium ovale B. Plasmodium malaria C. Plasmodium vivax D. Plasmodium falciparum 6. Life cycle of Plasmodium is A. Monogenetic B. Digenetic C. Trigenetic D. Polygenetic 7. Lifecycle of Plasmodium in human is in the sequence of A. Gametocytes → blood → asexual reproduction in liver cells → sexual reproduction in RBCs → release of hemozoin → sporozoites in RBCs B. Gametocytes → blood → sexual reproduction in liver cells → asexual reproduction in RBCs → release of hemozoin → sporozoites in RBCs C. Sporozoites → blood → asexual reproduction in liver cells → asexual reproduction in RBCs → release of hemozoin → gametocytes in RBCs D. Sporozoites → blood → sexual reproduction in liver cells → asexual reproduction in liver cells → release of hemozoin → gametocytes in RBCs 8. Stool with excess mucus & blood clots is the symptom of A. Amoebiasis B. Filariasis C. Ascariasis D. Taeniasis 9. Which is not desirable method of mosquito control? A. Avoid stagnation of water B. Use of mosquito nets C. Use of mosquito coil D. Introduce larvivorous fishes 10. Which of the following set of diseases can avoid through mosquito control? A. Malaria, Ascariasis, Tetanus and Dengue B. Chikun gunya, Dengue, Ringworm and Rabies C. Malaria, Dengue, Chikun gunya and Filariasis D. Filariasis, Diphtheria, Malaria and Dengue 11. Which of the following is transmitted through the serum? A. Hepatitis A B. Hepatitis B C. Venereal diseases D. Cirrhosis 12. What is true about Interferons? A. They are released by cells against viruses B. They are a group of hormone substances C. They are antibodies D. They are Viral proteins 13. Acquired immunity is A. Non- specific to pathogen and based on memory B. Pathogen specific but not based on memory C. Pathogen specific and based on memory D. Non-specific to pathogen and not based on memory 14. Treatment of snake-bite by antivenin is an example of A. Artificially acquired active immunity B. Artificially acquired passive immunity C. Naturally acquired passive immunity D. Specific natural immunity 15. Example for autoimmune disorders is A. Myasthenia gravis B. Rheumatoid arthritis C. AIDS D. Both A & B 16. The spread of cancer cells from one part of the body to another is called A. Metagenesis B. Metastasis C. Diapedesis D. Oncogenesis 17. For cancer detection, a thin piece of the suspected tissue is stained and examined under microscope. This is called A. Autopsy B. Necropsy C. Endoscopy D. Biopsy 18. For destroying cancer tumour, the patients are given biological response modifiers such as α- interferon. This kind of cancer treatment is known as A. Radiotherapy B. Chemotherapy C. Biopsy D. Immunotherapy 19. Any chemical that causes loss of sensation is A. Sedative B. Analgesic C. Anaesthetic D. Stimulant 20. Primary lymphoid organs are A. Bone marrow & thyroid B. Thymus & spleen C. Thymus & bone marrow D. Tonsils & thymus 21. Which of the following is not physiological barrier? A. HCl B. Lysozyme C. Saliva D. Mucus coating 22. Which is concerned with humoral immunity? A. Antibody B. T-cells C. B-cells D. Both A & C 23. The antibody present in colostrum is A. IgA B. IgD C. IgE D. IgG 24. Which is not true about CMI? A. It is mediated by B-lymphocytes B. It causes graft rejection C. It is a type of acquired immune response D. Helps to differentiate ‘self’ and ‘non-self’ 25. The best HLA (Human Leukocyte antigen) match for transplants in order of preference is A. Parent > sibling > twin > unrelated donor B. Sibling > twin > parent > unrelated donor C. Twin > sibling > parent > unrelated donor D. Sibling > parent > twin > unrelated donor 26. Drugs against allergy include A. Anti-histamine B. Adrenaline C. Steroids D. All the above