The immune system is the body's natural defense system, protecting it from foreign invaders such as bacteria, viruses, parasites, and cancerous cells. Without a strong immune system, a person would be easily susceptible to infection or disease. - How does the immune system work? The immune system is a complex network of organs, cells, and proteins that work together to detect and destroy any foreign invader or internal threat. This system includes: • White blood cells (leukocytes) – the first line of defense. These include: • Phagocytes – which engulf microbes. • Lymphocytes – which include two important types: • B cells – which produce antibodies. • T cells – which attack infected cells. • Lymphatic organs such as: • Spleen • Bone marrow • Lymph nodes • Thymus gland ⸻ 🧪 Types of Immunity 1. Innate Immunity: This is the immunity a person is born with, and it responds quickly to any threat. 2. Adaptive Immunity: This develops over time as a result of exposure to pathogens or after receiving vaccines. It is characterized by its accuracy and immunological memory. ⸻ 💉 Vaccines and Their Role in Supporting Immunity Vaccines train the immune system to recognize viruses or bacteria without becoming infected. Thus, upon future exposure, the body is prepared to attack them quickly and efficiently. ★ ⚠️ Weakened Immunity The immune system can be weakened by: • Chronic diseases such as diabetes and HIV/AIDS • Poor nutrition • Chronic stress • Lack of sleep • Certain medications such as corticosteroids ★ 🍎 Natural Ways to Boost Immunity • Eat a balanced diet rich in vitamins (especially C, D, and zinc) • Exercise regularly • Get enough sleep (7–8 hours) • Reduce stress • Drink plenty of water Al-Mustaqbal University, the leading university in Iraq