Life Processes

In order to enjoy a healthy life, all the life processes in our body must function well. A dysfunction in any of these processes can affect the working of other processes and the overall quality of life will be degraded.

The human heart consists of four chambers: two atria, which are the receiving chambers of the heart and two ventricles, which are the pumping chambers of the heart. A fish heart has two chambers and a frog heart has 3 chambers.

Digestion process involves the following steps: →Ingestion or the process in which food is taken in the body. →Digestion or the process in which complex food particles are broken down into simpler substances. →Absorption or the process in which the digested food is absorbed into the body. →The byproducts of metabolic reactions which are not useful for the body are eliminated through the process called excretion.

In fishes and reptiles, the heart is two-chambered and there is mixing of oxygenated and deoxygenated blood. They are cold blooded (the body temperature varies according to the surrounding temperature), so energy is required only for locomotion and hence less amount of oxygen is sufficient in them. Birds and mammals are warm blooded, so more energy is required to keep up the body temperature. To maintain high energy requirements of the body, more oxygen supply is required. Therefore, the heart has four chambers and oxygenated blood and deoxygenated blood is kept strictly separated. Also, complexities in the body structure and different mechanisms have increased with evolution. Therefore the mechanism of circulation has also evolved.

Glucose, amino acids, salts and high amount of water are reabsorbed in the nephron during the second step of urine formation, i.e., the selective reabsorption. These essential substances were filtered out from the blood in the first step called glomerular filtration and are reabsorbed as they are vital for the functioning of our body.

Nutrition in an amoeba occurs through a process called phagocytosis where the entire organism pretty much engulfs the food it plans on eating up. As amoeba is a unicellular organism, it does not have any specialized organ for the mechanism of nutrition. It directly swallows the whole food and a food vacuole is created. Digestive juices then get secreted in the vacuole and the food is slowly digested. After this, the waste is excreted.

Leaves of the plants have microscopic openings called stomata. These stomata help in the process of exchange of gases i.e., uptake of CO2 and release of by product of photosynthesis i.e., oxygen, into the atmosphere.

Platelets are tiny blood cells that help stop bleeding by forming clots. At the time of injury, when any blood vessels get damaged, it sends out signals. These signals are received by platelets and they, along with fibrinogen, a protein present in plasma form a clot and heal the wound.

Translocation is the transport of soluble products of photosynthesis. It occurs in the part of the vascular tissue known as phloem. The phloem also transports amino acids and other substances. These substances are especially delivered to the storage regions of roots, fruits and seeds and to growing regions.