Blood Groups

Depending upon the compatibility of antigen A and B with antibodies a and b, human blood can be classified into four groups: A, B, AB and O. Every human being has one of these blood groups. Blood transfusion is successful between the persons having some blood groups...

Blood Transfusion

The transfer of blood from a healthy person to another person is called blood transfusion. Blood transfusion is done, whenever there is loss of a lot of blood from the body due to an accident or during surgery. The healthy person who gives blood is called donor while...

Blood Clotting

 Clotting of blood is also called coagulation of blood. When a person gets injured, blood starts to flow out of the injury. But, after sometime blood solidifies at the site of injury and thus prevents the excessive loss of blood from the body. This is called clotting...

Blood Composition

In human body, various substances such as oxygen, digested food, hormones and enzymes are transported from one part of the body to other parts through blood and lymph. Blood is red in colour due to the presence of red coloured pigment called haemoglobin in it....

Phloem Vessels

The phloem vessels consist of sieve tubes and companion cells. Sieve tubesSieve tubes are long tubes which are made by end to end union of a large number of cells called sieve tube cells. The end walls of these cells are called sieve plates. These sieve plates bear...

Translocation of Food

In plants, food is prepared by the leaves by the process of photosynthesis. The food prepared by the leaves is in the form of simple sugars (glucose). No other part of the plant can prepare food. So, all the parts of a plant require food for getting energy,...