Major Systems of the Human Body and Their Functions" "Human Body Systems

Different Systems of the Body and Their Functions The human body functions smoothly due to the proper working of various systems. The major systems include the digestive system, respiratory system, circulatory system, and excretory system. Each system plays a crucial role in keeping the body healthy and active.

Digestive System The digestion process begins in the mouth. Teeth help in cutting and chewing food, while the tongue assists in turning it over. Properly chewing food (about 32 times) makes digestion easier. During chewing, saliva mixes with the food, converting it into a soft pulp. The food then reaches the stomach, where digestive juices help break it down further. The muscles of the stomach push the food towards the small intestine. In the small intestine, bile from the liver and pancreatic juice from the pancreas mix with the food. Special cells in the small intestine absorb the nutrients into the bloodstream. The remaining undigested food moves to the large intestine, where water is absorbed, and the waste is collected in the rectum. Eventually, this waste is excreted as feces. Excretory System The excretory system removes waste materials from the body through feces, urine, and sweat. Feces: The undigested and unused portion of food is expelled as feces. Urine: The kidneys filter harmful salts from the blood and excrete them as urine. The human body has two kidneys, which are roughly the size of kidney beans. Sweat: The skin helps remove excess salts and heat from the body through sweating. According to scientists, the body constantly releases sweat, but when air fails to evaporate it, sweat appears as droplets on the skin. Respiratory Process Oxygen is essential for all bodily functions. It enters the body and helps eliminate waste gases while generating energy. During respiration, air enters through the nostrils, where nasal hairs filter out dust particles and germs. The air then passes through the pharynx (throat) and larynx before entering the trachea. The trachea is made of ‘C’-shaped fibrous rings and divides into two branches, leading to the lungs. The lungs, protected by the rib cage, inhale fresh air and supply oxygen to the blood. They contain numerous air sacs with tiny pores, allowing gas exchange. Their flexible structure enables expansion and contraction. Circulatory System The circulatory system distributes oxygen and nutrients throughout the body. The heart plays a vital role in this process, functioning like a pump. Arteries: These carry oxygenated blood from the heart to various parts of the body. Veins: These bring deoxygenated blood back to the heart. Capillaries: These help filter blood and absorb nutrients. The heart is pear-shaped and is generally the size of a person’s fist. It continuously circulates blood, ensuring all body organs remain functional. Conclusion- For the body to function efficiently, every system must remain healthy. If any system becomes diseased, it affects the entire body. Therefore, a balanced diet, hygiene, and regular exercise are essential for maintaining a disease-free and active body.