All plants have resistance to some pathogens under cutin conditions. Different plants defend themselves against pathogens in different ways. The defense mechanism of plants against pathogens falls into two categories: 1. Morphological or Structural Defense Mechanism 2. Biochemical Defense Mechanism. 1. Morphological or Structural Defense Mechanism: The first line of defense against pathogens is the surface barriers which a pathogen [...]
Here is an essay on ‘Hypersensitivity Reactions’ for class 8, 9, 10, 11 and 12. Find paragraphs, long and short essays on ‘Hypersensitivity Reactions’ especially written for school and medical students. Essay on Hypersensitivity Reactions Immune reactions indicate a means of protection against infection due to development of specific resistance. Certain immunological reactions produce tissue damage during antigen and antibody [...]
Antigen (Ag) antibody (Ab) reactions occur when an antigen combines with a corresponding antibody to produce an immune complex. Therefore, an antigen-antibody reaction is thus a bimolecular association which is similar to an enzyme-substrate interaction but the only difference is that antigen-antibody reaction does not lead to an irreversible chemical interaction. The basis for antigen-antibody reactions are the non-covalent interactions [...]