Biology

Something which is’ living’ (not dead) is said to be ‘alive’. In most simple terms, alive’ means ‘having life’. Alive is called ‘jeevit’ or ‘zinda’ in Hindi. We are alive and you are also alive. Those things which are alive are called living things’. All the plants and animals (including human beings) are alive or … Read more

In human beings, many organs take part in the process of respiration. We call them organs of respiratory system. The main organs of human respiratory system are: Nose, Nasal passage (or Nasal cavity), Trachea, Bronchi, Lungs and Diaphragm. The human respiratory system begins from the nose. Our nose has two holes in it which are … Read more

Respiration can, however, also take place in the absence of oxygen (of air), though it is very rare. This means that oxidation of food to obtain energy can occur in the presence of oxygen as well as in the absence of oxygen. Based on this, we have two types of respiration : aerobic respiration and … Read more

Just like other organisms, plants also require food which can supply energy for their various metabolic activities. Though animals can move from one place to another in search of food, plants just stand still at one place and make their own food. Green plants are autotrophic and synthesize their own food by the process of … Read more

The nutrition in human beings (or man) takes place through human digestive system. The human digestive system consists of the alimentary canal and its associated glands. The various organs of the human digestive system in sequence are : Mouth, Oesophagus (or Food pipe), Stomach, Small intestine and Large intestine. The glands which are associated with … Read more

The organ system of human beings (and other animals) which is responsible for the transport of materials inside the body is called circulatory system. The various organs of the circulatory system in humans are: Heart, Arteries, Veins and Capillaries. Blood is also considered a part of the circulatory system. So, the human circulatory system consists … Read more

Like animals, plants also need energy. The plants get this energy by the process of respiration. Plants also use oxygen of air for respiration and release carbon dioxide. Thus, the respiration in plants also involves the exchange of oxygen and carbon dioxide. So, oxygen and carbon dioxide are called respiratory gases. The respiration in plants … Read more

Amoeba is a unicellular animal. Amoeba eats tiny (microscopic) plants and animals as food which float in water in which it lives. The mode of nutrition in Amoeba is holozoic. The process of obtaining food by Amoeba is called phagocytosis (‘Phagocytosis’ means ‘cell feeding’). The various steps involved in the nutrition of Amoeba are : … Read more

Food is an organic substance. The simplest food is glucose. It is also called simple sugar. A more complex food is starch. Starch is made from glucose. The general name of substances like glucose (sugar) starch. and starch is ‘carbohydrates’. Carbohydrates are the most common foods for getting energy. This is glucose powder. Glucose is … Read more