HUMAN HEALTH AND DISEASE Class XII Biology Malaria HIV Cancer

1. HUMAN HEALTH & DISEASE
PART- I
Dr Rama Kant Upadhyay
SOME COMMON DISEASES
MALARIA
AIDS

2. World Health Organization (WHO)
Health is a state of complete physical, mental and social well-being and not
merely the absence of disease or infirmity.
 Genetic disorders – deficiencies with which a child is born and deficiencies/defects
which the child inherits from parents from birth;
 Infections
 Lifestyle including food and water we take, rest and exercise we give to our bodies,
habits that we have or lack etc
Health is affected by

3. DISEASE
Any harmful deviation from the normal structural or functional state of an organism, generally
associated with certain signs and symptoms and differing in nature from physical injury.
https://www.pw.live/chapter-human-health-and-diseases/types-of-diseases

4. Disease-causing organisms are called pathogens
viruses, bacteria, fungi, protozoa, worms, etc
Pathogenicity is the potential disease-causing capacity of pathogens
Pathogen Disease
Viruses Common cold, Influenza, Measles, Mumps, Poliomyelitis, Rabies, Small pox, Chicken
pox, Yellow fever, AIDS etc.
Bacteria Cholera, Typhoid, Tuberculosis, Tetanus, Diphtheria, Pneumonia, Syphilis,
Gonorrhoea, Leprosy etc.
Protozoa Malaria, Amoebic dysentery, Sleeping sickness etc.
Fungi Ringworm, Athlete's foot etc.
Worms Filaria, Ascariasis, Cysticercosis, Pinworm
Mites Scabies

5. SOME COMMON DISEASES
Typhoid
Pneumonia
Common cold
Malaria
Amoebiasis (amoebic dysentery)
Ascariasis
Elephantiasis or Filariasis
Ringworms
AIDS

6. Pathogen- Salmonella typhii (Bacteria)
Diagnosis – Widal Test
Infected organ – GI tract
Vector - contaminated food and water
Symptoms- Sustained high fever (39° to 40°C), weakness,
stomach pain, constipation, headache and loss of appetite
Intestinal perforation may cause death
TYPHOID

7. • Pathogen - Streptococcus pneumoniae and Haemophilus influenzae
(Bacteria)
• Infected organ – Alveoli of lungs
• Transmission - inhaling the droplets/aerosols
• Symptoms - fever, chills, cough and headache, bluish nails, difficulty in
breathing
Pneumonia

8. Dysentery
 Pathogen- Shigella bacteria
 Infected organ – intestinal inflammation, especially in the colon
 Vector - contaminated food or water.
 Symptoms- bloody diarrhea, abdominal pain, cramps, fever
Plague
 Pathogen- Yersinia pestis bacteria
 Infected organ – Lungs
 Vector - Mice
 Symptoms- Difficulty or irregular breathing, sudden fever and chills, upset stomach and
vomiting, cough with bloody mucus, chest pain, bloody diarrhea, abdominal pain, cramps, fever
Common Cold
 Pathogen - Rhino viruses
 Infected organ - nose and respiratory passage
 Transmission - Droplets resulting from cough or sneezes
 Symptoms- nasal congestion and discharge, sore throat, hoarseness, cough, headache,
tiredness,

9. Amoebiasis (Amoebic Dysentery)
 Pathogen - Entamoeba histolytica (Protozoan)
 Infected organ - large intestine
 Transmission – Houseflies
 Drinking water and food contaminated by the faecal matter
 Symptoms- constipation, abdominal pain and cramps, stools with excess mucous and blood
clots
Ascariasis
 Pathogen Ascaris, the common round worm
 Infected organ - Intestine
 Transmission – contaminated water, vegetables, fruits
 Symptoms- internal bleeding, muscular pain, fever, anemia and blockage of the
intestinal passage
Elephantiasis or filariasis
 Pathogen Wuchereria (W. bancrofti and W. malayi)- Filarial worm
 Infected organ – Limbs , Genital organs
 Transmission – female mosquito vectors
 Symptoms- Chronic inflammation in lymphatic vessels of the lower limbs

10. MALARIA

11.  Pathogen Plasmodium (P. vivax, P. malaria and P. falciparum)- Protozoan
 Malignant malaria caused by Plasmodium falciparum can fatal.
 Hosts – Mosquito and Human
 Infective stage - Sporozoite
 Infected organ – Liver
 Transmission – female anopheles mosquito
 Symptoms- fiver with chill
 Sporozoites enter the body through the bite of an infected female Anopheles
mosquito.
 The parasites multiply within the liver cells and then attack the RBC.
 Rupture of RBCs causes the release of toxic haemozoin.
 Haemozoin is responsible for the chill and high fever recurring every three to four
days.
 When a female Anopheles mosquito bites an infected person, these parasites enter
the mosquito’s body.
 In the mosquito body the parasites multiply and form sporozoites.
 Sporozoites are stored in their salivary glands.
 When a mosquito bites a human they inject sporozoites into body.

13. Life cycle of Plasmodium
Stage 1- Gametocytes
Stage 2 Sporozoites
Stage 3 Merozoites
Gametocytes
 The male (micro) and female (macro) gametocytes are taken by female
anopheles mosquito during bite of infected person.
 These gametocyte fertilize in gut and form sporozoites.
 Sporozoites are stored in salivary gland of mosquito.
Sporozoites
 When the infected mosquito bite humans, the sporozoites enters into the
blood.
 After that, the sporozoites enter the liver cells and here they mature into
schizonts.
 Later, these sporozoites rupture and release merozoites.
Merozoites  The merozoites exit from the lever, entering the bloodstream again and here
they attack the RBC
 Certain merozoites develop into gametocytes
 When the red blood cells are destroyed by the merozoites, it releases
Hemazoin

15. AIDS
HIV

16.  Acquired Immuno Deficiency Syndrome
 Syndrome means a group of symptoms
 first reported in 1981
 caused by HIV
 Retrovirus - RNA genome
https://www.toppr.com/
 Test – enzyme-linked immunosorbent assay (ELISA)
 Treatment - Anti-retroviral drugs
 Symptoms- fever, diarrhea and weight loss
 World AIDS Day – 1st December

17. Transmission of HIV
• sexual contact with an infected person
• by transfusion of contaminated blood and blood products
• by sharing infected needles as in the case of intravenous drug abusers
• from infected mother to her child through the placenta
 The virus enters into macrophages where the RNA genome of the virus replicates to
form viral DNA with the help of the enzyme reverse transcriptase.
 This viral DNA gets incorporated into the host cell’s DNA and directs the infected cells
to produce virus particles.
 The macrophages continue to produce the virus and act as an HIV factory.
 Simultaneously, HIV enters into helperT lymphocytes, replicates, and produces
progeny viruses.
 The progeny viruses released in the blood attack other helper T-lymphocytes.
 This is leading to a progressive decrease in the number of helperT lymphocytes
in the body.

19. CANCER

20. Cancer is a group of diseases involving abnormal cell growth with the potential to invade or
spread to other parts of the body
• A tumor is a mass or lump of tissue that may resemble swelling.
• All tumors are NOT cancerous

21. TYPES OF TUMORS
Benign tumors – normally remain confined to their original location and do not
spread to other parts of the body and cause little damage.
Malignant tumors- a mass of proliferating cells called neoplastic or tumor cells.
These cells grow very rapidly, invading and damaging the surrounding normal tissues.
Metastasis: The spread of cancer cells from the place where they first formed to
another part of the body through blood.
Source: Drfly

22. Biological - Oncovirus has viral oncogenes, cellular oncogenes (c-onc) or proto-
oncogenes in normal cells c- onc activated lead to oncogenic transformation of the
cells.
Carcinogns
Physical - Ionising radiations like X-rays and gamma rays and non-ionizing radiations
Chemical – Tobacco
Cancer detection and diagnosis
• Biopsy
• Histopathological test
• Radiography (use of X-rays)- CT (computed tomography)
• MRI (magnetic resonance imaging)
• Endoscopy
• Biomarkers
• USG

23. Treatment of cancer
• Surgery - removes the tumor and nearby tissue during an operation
• Radiation therapy- uses high doses of radiation to kill cancer cells
• Chemotherapy - drug treatment that uses powerful chemicals to kill fast-growing
cells in your body.
• Biological response modifiers such as a-interferon which activates their immune
system and help in destroying the tumor, Immunotherapy.

24. THANK YOU