Title HUMAN HEALTH & DISEASE.pdf ✅

 Digital www.allendigital.in [ 71 ] 1. Introduction : Health : (i) Old view about health (i.e. Good humor hypothesis of health): • Asserted by : Early Greeks like Hippocrates as well as Indian Ayurveda system of medicine. • Health : State of body and mind, where there was balance of certain ‘humors’. Early Greeks like Hippocrates • Persons with ‘black bile’ belonged to hot personality and would have fevers. This idea was arrived at by pure reflective thought. Indian Ayurveda system of medicine • Disproved by : The discovery of blood circulation by William Harvey using experimental method and the demonstration of normal body temperature in persons with black bile using thermometer. (ii) Modern view about health: • Health ≠ absence of disease or physical fitness • Health: State of complete physical, mental and social well-being Blood Phlegm Yellow bile Black bile Body 4 humors 3 dosha Kapha Vata Pitta Body Mind / Mental state Influences through neural system and endocrine system Immune system maintains Health Human Health and Disease 02
NEET : Biology [ 72 ] www.allendigital.in  Digital (iii) Health is affected by: (i) Genetic disorders : Deficiencies with which a child is born and deficiencies / defects which the child inherits from parents from birth (ii) Infections (iii) Life style : • Food and water we take • Rest and exercise we give to our bodies • Habits that we have or lack • e.g. Drug and alcohol abuse also affect our health adversely. (iv) Benefits of being healthy: • Efficiency at work  → Productivity  → Economic prosperity • Longevity  • Infant and maternal mortality  (v) Very important to maintain good health:  Balanced diet  Personal hygiene  Regular exercise Yoga : Yoga has been practised since time immemorial to achieve physical and mental health. (vi) Necessary for achieving good health: • Awareness about diseases and their effect on different bodily functions. • Vaccination (immunisation) against infectious diseases. • Proper disposal of wastes. • Control of vectors. • Maintenance of hygienic food and water resources. Disease: • Functioning of one or more organs or systems of the body is adversely affected. • Characterised by various signs and symptoms. 2. Classification of diseases : • Diseases can be broadly grouped into infectious and non-infectious : Diseases Infectious/Communicable (spread from one person to another person) Non-infectious/Non-communicable (will not spread from one person to another person) Congenital diseases Acquired diseases Contagious (by direct contact) Non-contagious (by indirect contact)
Human Health and Disease  Digital www.allendigital.in [ 73 ] 3. Common Diseases in Humans : Introduction to common diseases in humans Pathogens : • Pathogens are disease causing organisms (belonging to bacteria, viruses, fungi, protozoans, helminths, etc.). • Most parasites are therefore pathogens as they cause harm to the host by living in (or on) them. • Pathogens have to adapt to life within the environment of the host. e.g. The pathogens that enter the gut must know a way of surviving in the stomach at low pH and resisting the various digestive enzymes. How do pathogens create their pathogenicity inside our body? Entry of pathogen into our body by various means  Multiplication of pathogen and interference with normal vital activity of our body  Morphological and functional damage to our body Examples of infectious diseases in humans : Type of disease Examples Bacterial Typhoid, Pneumonia, Dysentery, Plague, Diphtheria, Tuberculosis, Whooping cough (Pertussis), Cholera, Leprosy, etc. Viral Common cold, Dengue, Chikungunya, Polio or Poliomyelitis, Influenza, Measles, Chicken pox, Mumps, Rabies, SARS (Severe Acute Respiratory Syndrome), Swine flu, Covid 19, etc. Protozoan Malaria, Amoebiasis (Amoebic dysentery), etc. Helminthic Ascariasis, Elephantiasis (Filariasis), etc. Fungal Ringworms, etc. S.No. Bacterial Diseases Pathogen Symptoms & Pathogenicity (1) Typhoid fever Salmonella typhi • Enters small intestine through contaminated food and water and migrate to other organs through blood • Sustained high fever (39-40°C) • Weakness, constipation, stomach pain • Headache, loss of appetite • In severe cases intestinal perforation, death • Widal test • Mary Mallon, Nicknamed- Typhoid Mary (Carrier of typhoid) TG: @Chalnaayaaar
NEET : Biology [ 74 ] www.allendigital.in  Digital (2) Pneumonia Streptococcus pneumoniae Haemophilus influenzae • By droplet or aerosol infection or use of glass or utensils of infected person • Infects alveoli of the lungs • Alveoli get filled with fluid leading to severe problem in respiration • Fever with chills, cough & headache • In severe cases lips and nails turns gray to bluish in colour (3) Dysentery (Shigellosis) Shigella dysenteriae • Abdominal pain • Blood & mucus in the stool • Transmits through faecal oral route (4) Plague (Black death) Yersinia pestis Parasite of Xenopsylla cheopis (Rat flea) • High fever, headache • Enlargement of axillary lymph nodes • Pneumonic (lungs)...... septa between alveoli rupture • Septicemic (blood poisoning)... Black Death (5) Diphtheria Corynebacterium diphtheriae • High grade fever, affects throat • Causes suffocation (Investigation : Schick test) (6) Tetanus (Lock jaw) Clostridium tetani • Sustained contraction of body muscles, spasms, lock jaw, unconsciousness, opisthotonus & Risus Sardonicus - Stretching of facial muscles & neck-back muscles. S.No. Viral Diseases Pathogen Symptoms & Pathogenicity (1) Common cold Rhino viruses (Group of viruses) (ss RNA) • One of the most infectious human ailments • Transmits through droplet resulting from cough, sneeze etc. • Infect nose and respiratory passage but not the lungs • Nasal congestion and discharge, sore throat, hoarseness, cough, headache, tiredness (2) Chikun-gunya Chikungunya virus (ss-RNA) (Vector :- Aedes- ageypti mosquito) • Fever, joint pain, Lymphoadenopathy (enlargement of lymph nodes) (3) Dengue fever or Break-bone- fever Flavi-arbo virus (Vector :- Aedes- ageypti mosquito) • Fever, severe-frontal-headache, muscle & joint pain • Bleeding from nose, mouth, gums (4) Hepatitis-B HBV (ds DNA) • Severe liver damage, jaundice • Recombinant DNA-vaccine • Transmits-through parenteral and sexual- route • Can cross placenta