Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
AIDS (Acquired Immuno Deficiency Syndrome) is caused by the Human Immunodeficiency Virus (), which belongs to the group of viruses called retroviruses having an genome enveloped in a protein coat.
The life cycle involves the conversion of viral into viral using the enzyme . This then incorporates into the host cell's to direct the production of virus particles.
In infected individuals, replicates in macrophages (acting as an factory) and attacks Helper T-lymphocytes ( cells), significantly reducing the cell count.
Diagnosis of AIDS is typically done using (Enzyme-Linked Immunosorbent Assay) and confirmed by Western Blotting.
Cancer is characterized by the breakdown of regulatory mechanisms of cell growth and differentiation. Normal cells show 'contact inhibition', a property lost by cancer cells.
Tumors are classified into two types: Benign (remain confined to original location) and Malignant (mass of proliferating cells called neoplastic cells that exhibit metastasis).
Metastasis is the most feared property of malignant tumors, where cells sloughed from tumors reach distant sites via blood and start new tumors.
Cancer is caused by carcinogens: Physical (-rays, rays), Chemical (tobacco smoke), and Biological (Oncogenic viruses containing viral oncogenes or activation of proto-oncogenes/).
Cancer detection techniques include Biopsy, Histopathological studies, Radiography (-rays), (Computed Tomography) using imaging, and (Magnetic Resonance Imaging) using strong magnetic fields and non-ionizing radiations.
Treatment of cancer involves a combination of Surgery, Radiotherapy, Chemotherapy, and Immunotherapy (using biological response modifiers like ).
📐Formulae
💡Examples
Problem 1:
A patient shows a significantly low count of lymphocytes and tests positive in an test. Identify the disease and explain why the patient becomes vulnerable to infections like Mycobacterium and fungal pathogens.
Solution:
The patient is suffering from AIDS ().
Explanation:
The virus attacks and destroys Helper T-lymphocytes ( cells). As the number of cells decreases, the body's cell-mediated immune response weakens. Consequently, the patient cannot produce sufficient antibodies or activate macrophages/killer T-cells, leading to opportunistic infections by , viruses, fungi, and parasites like .
Problem 2:
Differentiate between Benign and Malignant tumors based on their growth and movement in the body.
Solution:
Benign tumors are localized, while Malignant tumors exhibit metastasis.
Explanation:
Benign tumors remain confined to their original location and do not spread to other parts of the body, causing little damage. Malignant tumors consist of neoplastic cells that grow rapidly, invade surrounding tissues, and compete for vital nutrients. These cells can slough off and reach distant sites through blood, a process called metastasis, forming secondary tumors.