Human Health and Diseases Class 12 | Biology NCERT Chapter 7 One Shot | CBSE NEET LearnoHub - Class 11, 12・2 minutes read
Health encompasses physical, mental, and social well-being, achieved through yoga, exercise, and a balanced diet. Diseases like typhoid, malaria, pneumonia, and ringworm require specific diagnosis and treatment, emphasizing the importance of maintaining good health to prevent illnesses.
Insights Health encompasses physical, mental, and social well-being, achieved through yoga, exercise, and a balanced diet. Diseases are categorized as infectious or non-infectious, with common examples like typhoid, malaria, and pneumonia having distinct causes, symptoms, and treatments. The immune system plays a vital role in protecting against diseases, with lymphocytes producing antibodies to combat pathogens through humoral and cell-mediated immunity. AIDS and cancer are severe health conditions with distinct causes, symptoms, and treatments, emphasizing the importance of prevention and early diagnosis for effective management. Get key ideas from YouTube videos. It’s free Recent questions What is the definition of health?
Health is complete physical, mental, and social well-being.
Summary 00:00
"Complete Health: Physical, Mental, Social Well-being" Health is defined as complete physical, mental, and social well-being. Physical well-being involves being disease-free and physically fit. Mental well-being requires peace of mind, absence of stress, anxiety, and depression. Social well-being entails good relationships with friends and neighbors. Maintaining good health involves yoga, physical exercise, and a balanced diet. Yoga is both a physical and spiritual discipline that enhances mental and physical well-being. Physical exercise, like walking, jogging, or sports, boosts energy and flexibility. A balanced diet includes fruits, vegetables, dairy, protein-rich foods, and whole grains in appropriate amounts. Diseases disrupt the body's normal functioning, leading to symptoms and signs. Diseases are categorized as infectious (communicable) or non-infectious (non-communicable), based on their ability to spread from person to person. 15:37
Mosquitoes transmit diseases like typhoid and malaria. Mosquitoes transmit diseases by sucking blood and injecting pathogens into the body. Common diseases affecting humans include typhoid, malaria, pneumonia, scarious, and ringworm. Typhoid is caused by Salmonella typhi, leading to symptoms like high fever, headache, weakness, and loss of appetite. Typhoid is diagnosed through blood or urine culture tests, including the Widal test. Antibiotics are used to treat bacterial infections like typhoid, not viral infections. Pneumonia is caused by Streptococci pneumonia and Haemoflagellates, affecting the lungs and leading to symptoms like cough, fever, chills, weakness, and shortness of breath. Pneumonia is diagnosed through chest X-rays, urine tests, and mucus tests, and treated with antibiotics. The common cold is a viral infection spread through contaminated air and objects, affecting the nasal passages and causing symptoms like runny nose, sore throat, cough, and hoarse voice. Treatment for the common cold includes nasal sprays, nasal drops, and painkillers, as antibiotics are ineffective against viral infections. Malaria is caused by Plasmodium parasites transmitted through mosquito bites, leading to symptoms like fever. 30:46
"Malaria: Transmission, Symptoms, Diagnosis, Treatment, Prevention" Female Anopheles Mosquitoes are the only ones capable of transmitting malaria parasites into the human body. Malaria symptoms include high fever, chills, headaches, body aches, nausea, and vomiting. Malaria diagnosis involves blood tests and liver function tests to detect the presence of the parasite. Antimalarial drugs are available in the market for treating malaria effectively. The life cycle of a malarial parasite involves transmission from mosquitoes to humans, leading to the spread of the disease. The malarial parasite enters the human body through mosquito bites, transmitting gametocytes and spores. Spores released by the parasite multiply in the human body, affecting red blood cells and causing symptoms of malaria. The malarial parasite uses both humans and mosquitoes as hosts in its life cycle. A similar transmission process is explained for amoebic dysentery, where contaminated food and water spread the infection through house flies. Prevention of amoebic dysentery involves maintaining cleanliness and hygiene in food and water consumption. 46:20
Preventing Disease: Steroids, Antibiotics, and Hygiene Steroids are given to everyone for treatment. Antibiotics can be used for worms that are bacteria. Antibiotics are effective against bacteria only. Ringworm is caused by a fungus called Phyton. Ringworm symptoms include dry, itchy skin with red patches. Anti-fungal drugs like creams can treat ringworm. Personal cleanliness and not sharing personal items can prevent infectious diseases. Proper disposal of excreta and clean drinking water are crucial for disease prevention. Washing fruits and vegetables before consumption helps prevent infections. Using mosquito repellents and insecticides in drainage areas can prevent disease spread. 01:02:24
Understanding Immune System: Memory, Cells, Antibodies The body's immunity system protects against disease-causing organisms by storing memory of past attacks. Acquired immunity involves primary and secondary responses to pathogen attacks. Primary response is low intensity, while secondary response is high intensity due to memory of past attacks. Lymphocytes, including B and T cells, play a crucial role in immune responses. B lymphocytes produce antibodies to neutralize pathogens, while T lymphocytes stimulate B cells. Antibodies are Y-shaped proteins that recognize and neutralize antigens, preventing their harmful effects. Antigens are foreign substances that trigger the production of antibodies by B lymphocytes. B cells include plasma B cells that produce antibodies and memory B cells that respond quickly to subsequent attacks. T cells, like helper T cells, assist in stimulating B cells to produce antibodies in cell-mediated immunity. Humoral immunity involves antibodies in the blood, while cell-mediated immunity relies on cells to combat pathogens without antibody production. 01:18:18
"Immune System, Transplantation, Vaccination: Key Concepts" The immune system of the body is crucial for distinguishing between self and non-self, leading to rejection of foreign organs like kidneys. Blood group and tissue matching are essential before transplantation to prevent rejection by the body. Immunosuppressants are given to transplant patients to boost their immune response and prevent rejection. Active immunity involves the production of antibodies inside the body, as seen in cases like chickenpox or hepatitis A. Vaccination introduces a weakened or dead form of a microbe into the body to trigger an immune response and build immunity. Natural active immunity occurs when a person naturally contracts a disease and develops antibodies against it. Artificial active immunity is achieved through vaccines, where the body produces antibodies without contracting the disease. Natural passive immunity happens when antibodies are passed from mother to child, while artificial passive immunity involves injecting antibodies directly into the body. Vaccination schedules are crucial to ensure the effectiveness of vaccines, especially for children. Vaccination has been instrumental in eradicating diseases like smallpox and reducing the prevalence of others like measles, showcasing its effectiveness in disease prevention. 01:33:32
Understanding Allergies: Causes, Symptoms, and Treatments Allergens cause agitation in the body, leading to allergic reactions. Mast cells release chemicals like histamine and serotonin during an allergic response. Mast cells are immune cells found in tissues and along blood vessels. The immune system produces antibodies, like immunoglobulin, in response to allergens. When allergens interact with mast cells, granules are released, causing allergic symptoms. Allergic reactions occur when the body encounters allergens like dust, pollen, or perfume. Symptoms of allergies include watery eyes, runny nose, breathing difficulties, and sneezing. Anti-allergen drugs can be used to alleviate severe allergy symptoms. The human immune system consists of lymphocytes, which produce antibodies to fight antigens. Lymphoid organs like the bone marrow, thymus, spleen, lymph nodes, tonsils, and Peyer's patches play crucial roles in the immune response. 01:49:13
Understanding AIDS: Causes, Symptoms, and Prevention AIDS is caused by the human immunodeficiency virus (HIV), targeting the immune system, making even a mild cold fatal. Transmission of AIDS occurs through sexual contact, contaminated blood transfusion, and from an affected mother to her child. The virus spreads through blood transfusion, affected needles, and from an affected mother to her child via the placenta. HIV is a retrovirus that enters host cells, undergoes reverse transcription, and replicates, leading to a decrease in T cells and macrophages. Symptoms of AIDS include diarrhea, fever, weight loss, and minor infections turning fatal due to the immune system being targeted. AIDS can be diagnosed through an Elisa test, and treatment involves anti-retroviral drugs to reduce the number of viruses in the body. Prevention of AIDS transmission includes using condoms, avoiding multiple sex partners, ensuring partners are HIV tested, and using disposable needles. Cancer is abnormal cell growth and division leading to the formation of tumors that disrupt normal body functioning. Tumors can be benign, limited to one area, or malignant, spreading to other parts of the body through blood or lymphatic system. Benign tumors grow locally, while malignant tumors spread rapidly to other body parts, impacting normal body functions. 02:04:31
Understanding Cancer: Growth, Spread, and Treatment Lymph spreads throughout the body, connecting different parts and can spread from one place to another. Malinators are lymph cells that continue to grow without limits, causing traffic problems in the body. Malinators are harmful as they grow and spread, damaging healthy tissues and causing tumors. Metastatic cancers are cancers that grow and spread to other body parts, damaging healthy tissues. Carcinogens are agents that turn normal cells into cancerous cells, such as ultraviolet radiation and oncogenic viruses. Cancer can have genetic links, increasing the risk of cancer but not guaranteeing its occurrence. Cancer diagnosis involves techniques like biopsies and scans like MRI, CT, and PET scans to detect cancer cells. Cancer treatment includes surgery to remove cancerous cells, chemotherapy to destroy cancer cells, and radiotherapy to kill cancer cells with radiation. The type of cancer treatment depends on the stage and type of cancer, sometimes involving a combination of surgery, chemotherapy, and radiotherapy. Chemotherapy has side effects but with advancements, treatments are improving, and early diagnosis through regular check-ups is crucial for effective treatment. 02:20:15
Dangers of Drugs, Tobacco, and Alcohol Heroin is a chemical compound extracted from the latex of the poppy plant, acting as a depressant that slows down bodily functions. Cannabinoids, obtained from the cannabis plant, impact the brain by binding to receptors, affecting memory, thinking capabilities, and coordination. Cocaine, an alkaloid from the cocoa plant, is a strong CNS stimulant that increases dopamine levels, providing extra energy but leading to negative long-term effects. Tobacco, containing nicotine, is harmful when smoked, chewed, or snuffed, impacting the lungs, respiratory system, blood pressure, adrenal glands, and potentially causing cancer and heart disease. Peer pressure, trendiness, and curiosity are common reasons why youth turn to drugs, alcohol, or tobacco, leading to addiction due to the effects on the central nervous system. Social gatherings often involve the consumption of harmful substances like drugs, tobacco, or alcohol, causing long-term harm to the body. It is crucial to be cautious of adopting harmful habits from others and to understand the severe adverse effects of substances like drugs, tobacco, and alcohol on health.