Tag: zoology

Hay fever and asthma are the allergic reactions of the body to allergens. Allergy is the hypersensitivity of a person to some foreign substance coming in contact with the body. 

The nematodes or roundworms constitute the phylum Nematoda and have a pseudocoelom and complete digestive system. The partial, fluid-filled cavity inside the body of some invertebrates. Cnidarians have two different body plans. Both body plans have radial symmetry. A polyp, such as a hydra, sea anemone, or coral, is shaped something like a vase. Platyhelminthes, a group of soft-bodied, usually much flattened invertebrates and have cavity only one opening to the outside which, in most cnidarians, is surrounded by tentacles for capturing prey. But Porifera does not have a gastrovascular cavity as it does not have specialized tissues and phyla with a true coelom and digestive system. The protostomes include the phyla Mollusca, Annelida, and Arthropoda but not porifera. 

Edward Jenner is known as father of immunology due to his discovery of famous small pox vaccine which was also the first successful vaccine to be developed and helped in the eradication of disease completely. 

The specific defence system has immunity to specific microbes and antigens hence it is a potent body response and can produce humoral ,oral,lymphoid immunity etc.

Passive immunity is the type of immunization when a ready-made antibody is directly given to the patient to protect the body against foreign attack. It can be injected artificially or provided naturally by mother milk (colostrum) or by transferring it to the foetus by the placenta.

• Immunity tolerance, or immunological tolerance, or immune tolerance, is a state of unresponsiveness of the immune system to substances or tissue that have the capacity to elicit an immune response in a given organism or It is the prevention of an immune response against a particular antigen.
• For example, the immune system is generally tolerant of self-antigens, so it does not usually attack the body's own cells, tissues, and organs. However, when tolerance is lost, disorders like autoimmune disease or food allergy may occur.
  
• Hence Immunity tolerance is developed by interaction with the antigen.
• So, the correct answer is 'Interaction with the antigen'.

Immunity is said to be passive when antibodies produced in other organisms (their sera) are injected into a person who already has a potential antigen in his body. Administration of antibody against tetanus, botulism etc. makes large amounts of antitoxin immediately available to neutralize the toxins.

Protective mechanical barriers include skin, hair, mucus etc. Skin has an outer tough layer made of a protein keratin and is almost impermeable to germs.