The following are some important subtopics related to “Biology In Human Welfare - Human Health And Disease” that are commonly covered while preparing for the JEE exam:

1. Health and Disease:

• Health: A state of complete physical, mental, and social well-being, not merely the absence of disease (NCERT Biology Class 11, Chapter 1 - The Living World).

• Disease: A condition characterized by abnormal changes in the body’s structure or function, resulting in discomfort, dysfunction, or even death (NCERT Biology Class 11, Chapter 1 - The Living World).

Types of Diseases:

• Communicable Diseases: Spread from one person to another or from animals to humans through various means (NCERT Biology Class 12, Chapter 13 - Organisms and Populations):

• Examples: Influenza, Malaria, Tuberculosis, COVID-19.

• Non-Communicable Diseases: Not transmitted from person to person but arise due to genetic, environmental, or lifestyle factors (NCERT Biology Class 11, Chapter 2 - Biological Classification):

• Examples: Cancer, Diabetes, Cardiovascular diseases, Asthma, etc.

2. Types of Diseases and Disorders:

Infectious Diseases:

• Caused by microorganisms like viruses, bacteria, fungi, or parasites that enter the body and disrupt normal functions (NCERT Biology Class 12, Chapter 15 - Biodiversity and Conservation):
• Viral Diseases: Influenza, Measles, Mumps, AIDS, etc.
• Bacterial Diseases: Tuberculosis, Cholera, Typhoid, Pneumonia, etc.
• Fungal Diseases: Athlete’s Foot, Ringworm, Candidiasis, etc.
• Parasitic Diseases: Malaria, Amoebiasis, Filariasis, etc.

Non-Communicable Diseases:

a) Lifestyle-related disorders:

• Predominantly caused by unhealthy lifestyle choices and habits (NCERT Biology Class 12, Chapter 6 - Reproduction):
• Cardiovascular Diseases: Hypertension, Heart attacks, Strokes.
• Diabetes: Type 1 and Type 2 Diabetes Mellitus.
• Cancer: Various types of cancers (lung, breast, colon, etc.)
• Chronic Respiratory Diseases: Chronic Obstructive Pulmonary Disease (COPD), Asthma.
• Obesity: Excessive accumulation of body fat.
• Mental Disorders: Depression, Anxiety, Schizophrenia, etc.

b) Genetic Disorders:

• Caused by abnormalities in genes or chromosomes (NCERT Biology Class 12, Chapter 5 - Principles of Inheritance and Variation):
• Down Syndrome: Trisomy of chromosome 21.
• Cystic Fibrosis: Recessive genetic disorder affecting the lungs and digestive system.
• Sickle Cell Anemia: Inherited blood disorder that affects the structure and function of red blood cells.
• Hemophilia: Inherited blood-clotting disorder due to deficiency of clotting factors.

c) Autoimmune Disorders:

• Immune system mistakenly attacks the body’s own tissues and cells, leading to various disorders (NCERT Biology Class 12, Chapter 22 - Immune System):
• Rheumatoid arthritis: Affects the joints.
• Multiple Sclerosis: Affects the central nervous system.
• Type 1 Diabetes Mellitus: Affects the pancreas and insulin production.
• Lupus: A systemic autoimmune disorder affecting multiple organs and systems.

3. Immune System and Immunity:

• Innate Immunity: Defense mechanisms present from birth that provide immediate but nonspecific protection (NCERT Biology Class 12, Chapter 22 - Immune System):

• Physical barriers: Skin, mucous membranes, stomach acid, saliva, tears, etc.

• Cellular components: Phagocytes (neutrophils, macrophages), Natural killer (NK) cells.

• Chemical components: Antimicrobial substances, Interferons.

• Acquired Immunity: Develops in response to exposure to specific pathogens and provides long-term protection (NCERT Biology Class 12, Chapter 22 - Immune System):

• B cells: Produce antibodies to neutralize specific antigens.

• T cells: Recognize and destroy infected cells or cancer cells.

• Macrophages: Phagocytose antigens and present them to T cells.

• Memory cells: Provide long-term immunity against specific pathogens.

• Active vs. Passive Immunity: Active immunity is acquired by vaccination, where the body produces its own antibodies. Passive immunity is acquired by receiving antibodies from another organism (e.g., through breastfeeding or serum therapy).

Immune Disorders:

• Allergies: Overactive response of the immune system to harmless substances.
• Autoimmune Diseases: Improper functioning of immune cells, leading to attacks on self-tissues.
• Immunodeficiency Disorders: Weakened immune response, leading to increased susceptibility to infections.

4. Genetics and Diseases:

• Patterns of Inheritance:

• Mendelian Inheritance: Dominant and recessive traits, law of segregation, law of independent assortment.

• Polygenic Inheritance: Involves multiple genes contributing to a single trait.

• Chromosomal Abnormalities: Changes in chromosome number (aneuploidy) or structure (deletion, duplication, translocation, inversion).

• Genetic Diseases and Disorders:

• Single Gene Disorders: Cystic fibrosis, sickle cell anemia, hemophilia, Huntington’s disease, etc.

• Chromosomal Disorders: Down syndrome, Turner syndrome, Klinefelter syndrome, etc.

• Genetic Counseling and Prenatal Diagnosis:

• Genetic counseling: Provides information and support to individuals and families with genetic disorders.

• Prenatal diagnosis: Tests performed during pregnancy to identify genetic abnormalities in the fetus.

5. Diagnostic Techniques and Treatment Strategies:

• Microscopy: Use of microscopes to observe microorganisms, cells, and tissues (NCERT Biology Class 11, Chapter 2 - Biological Classification).

• Light microscopy: Uses visible light.

• Electron microscopy: Uses a beam of electrons to provide higher magnification and resolution.

• Serological Techniques:

• ELISA (Enzyme-Linked Immunosorbent Assay): Detects and quantifies substances like antibodies, antigens, or hormones in a sample.

• Western blotting: Separates and identifies specific proteins in a sample.

• Molecular Diagnostic Techniques:

• PCR (Polymerase Chain Reaction): Amplifies specific DNA sequences for detection or analysis.

• DNA sequencing: Determines the sequence of nucleotides in a DNA sample, allowing the identification of genetic mutations or variations.

• Treatment Options:

• Medications: Drugs and medicines to treat symptoms or target the underlying cause of a disease.

• Surgery: Physical intervention to remove or repair damaged tissue or organs.

• Radiotherapy: Uses high-energy radiation to kill cancer cells.

• Chemotherapy: Uses cytotoxic drugs to kill cancer cells.

• Immunotherapy: Stimulates the immune system to recognize and destroy cancer cells.

6. Public Health and Epidemiology:

• Epidemiology:

• Study of disease patterns: Includes factors such as disease occurrence, distribution, causes, and control (NCERT Biology Class 12, Chapter 13 - Organisms and Populations).

• Factors affecting disease prevalence: Environmental conditions, socio-economic status, hygiene practices, behavior, etc.

• Public Health Measures:

• Vaccination programs: Immunize populations against specific infectious diseases.

• Sanitation and hygiene practices: Provision of clean water, proper waste management, hand hygiene, etc.

• Vector control: Measures to control or eliminate disease-carrying organisms (e.g., mosquitoes, rats).

• Quarantine and Isolation: Restricting the movement of individuals or groups to prevent the spread of infectious diseases.

Remember to follow the NCERT Biology textbooks for 11th and 12th classes as your primary resource for in-depth understanding and further details on the above-mentioned subtopics when preparing for the JEE exam.