Advanced study of circulatory system, transportation, excretion, and homeostasis. Learn how organisms maintain internal balance and survive in changing environments.
Life Processes – II focuses mainly on circulatory system, transportation, excretion, and plant life processes in more detail. These processes help organisms maintain internal balance and survive in changing environments.
Transportation is the process by which oxygen, nutrients, hormones, and waste materials are carried from one part of the body to another.
Blood is a fluid connective tissue that circulates throughout the body.
| Component | Function | Characteristics |
|---|---|---|
| Red Blood Cells (RBCs) | Transport oxygen using haemoglobin | Biconcave shape, no nucleus, red color |
| White Blood Cells (WBCs) | Fight infections and provide immunity | Colorless, nucleated, larger than RBCs |
| Platelets | Help in blood clotting | Tiny, irregular cell fragments |
| Plasma | Liquid part that carries nutrients, hormones, wastes | Yellowish fluid, 55% of blood volume |
The heart is a muscular organ that pumps blood throughout the body.
[Diagram of Human Heart with chambers labeled]
Four chambers: Right atrium, Right ventricle, Left atrium, Left ventricle
| Blood Vessel | Direction of Blood Flow | Characteristics | Function |
|---|---|---|---|
| Arteries | Away from heart | Thick, muscular walls, no valves | Carry oxygenated blood (except pulmonary artery) |
| Veins | Towards heart | Thinner walls, have valves | Carry deoxygenated blood (except pulmonary vein) |
| Capillaries | Connecting arteries and veins | Very thin walls (one cell thick) | Exchange of materials between blood and tissues |
Plants need to transport water, minerals, and prepared food to all parts of their body.
Key Difference: Xylem transports water and minerals upward only, while phloem transports food in both directions.
Excretion is the removal of metabolic waste products from the body.
[Diagram of Human Excretory System]
Showing kidneys, ureters, urinary bladder, and urethra
Nephron is the structural and functional unit of the kidney. Each kidney contains about 1 million nephrons.
[Diagram of Nephron Structure]
Showing glomerulus, Bowman's capsule, tubules, and collecting duct
Plants remove waste materials through various methods:
Homeostasis is the ability of an organism to maintain stable internal conditions such as temperature, water balance, and pH despite changes in the external environment.