1. Every antibody is designed to target a specific antigen. 2. Interaction occurs between antigenic determinants (epitopes), situated on the combining sites of antigens, and the corresponding paratopes on antibodies. 3. The variable regions of antibodies house the antigen-binding sites (paratopes). 4. Minute differences in the variable regions contribute to the high specificity of each … Read more
Antigens on Blood Cells: Blood cells, comprising red blood cells (erythrocytes), white blood cells (leukocytes), and platelets, exhibit distinct antigens on their surfaces. These antigens play a pivotal role in blood typing and compatibility. 1. Red Blood Cell Antigens (Blood Group Systems): •ABO System: In the ABO blood group system, red blood cells express antigens known … Read more
Each ovule develops within the ovary, connected to the placenta by a small stalk known as the funiculus. The point where the funiculus attaches to the main body of the ovule is termed the hilum. In angiosperms, the prevalent ovule type is anatropous, with the micropyle directed downward and situated next to the funiculus (funicle). … Read more
The immature stage of an anther is characterized by a parenchymatous tissue group enclosed by a single-layered epidermis. Anthers are typically dithecous (with two lobes) and tetrasporangiate. A monothecous anther holds two pollen sacs, while a dithecous anther has four, making it tetrasporangiate. Heterogeneity in differentiation occurs when certain hypodermal cells undergo transformation into archesporial … Read more
1. Fatigue: Feeling persistently tired or lacking energy. 2. Lumps or Thickening:Detecting an abnormal lump or thickened area under the skin 3. Weight Changes:Experiencing unintended weight loss or gain. 4. Skin Changes: Noticing alterations like yellowing, darkening, redness, non-healing sores, or changes in moles. 5. Altered Habits:Changes in bowel or bladder habits, persistent cough, difficulty … Read more
HIV is transmitted for following reasons: 1. HIV transmission occurs through specific activities such as sex or injection drug use. 2. The virus is transmitted via certain body fluids, including blood, semen, pre-seminal fluids, rectal fluids, vaginal fluids, and breast milk. 3. Transmission is possible only if these fluids contact mucous membranes, open cuts or … Read more
Malaria symptoms typically manifest 7 to 18 days post-infection. Common signs include fever, fatigue, chills, vomiting, headaches, diarrhea, anemia, and muscle pain. Severe cases may involve profuse sweating, convulsions, and, in extreme instances, seizures, coma, or death. Malaria is spread for the following reason: When a mosquito contracts a disease from biting an infected person … Read more
B Cells (B Lymphocytes): 1. Originate in the bone marrow. 2. Also known as B lymphocytes. 3. Present inside lymph nodes. 4. Have surface antibodies. 5. Connect to the surface of invading bacteria and viruses. 6. Membrane receptor for antigen is BCR (B cell receptor). 7. Life span is short. 8. Secrete antibodies. 9. Have … Read more
Comparing Active Immunity and Passive Immunity: Active Immunity: Protection Origin: Originates from the body’s response to antigens, leading to antibody production and memory cell formation. Duration of Protection: Offers prolonged defense, often for years or a lifetime. Induction: Triggered by exposure to a pathogen through infection or vaccination. Primary Response: Initial immune response is slower as … Read more
Carcinogens are substances that induce cancer and can be classified into physical, chemical, and biological agents. Carcinogen Organ affected I. Coal tar (3, 4 benzpyrene) Skin, lungs ii. Cigarette smoke (N-nitrosodimethylamine) Lungs iii. Cadmium oxide Prostate gland iv. Aflatoxin (a metabolite of Aspergillus flavus, a mould) Liver