Platelets or thrombocytes in animals Platelets or thrombocytes in animals are disk-shaped structures, derived from the megakaryocytes of the bone marrow. Mammalian platelets are non-nucleated, whereas they are nucleated in birds and reptiles. In mammals, platelets originate from the megakaryocytes of the bone marrow and In birds they arise from large mononucleated cells of bone […]
Antibodies in animals Antibodies are the gamma globulins or immunoglobulins made up of a combination of light and heavy polypeptide chains. Each heavy chain is paralleled by a light chain at one of its end, which form the variable portion. This variable region with both light and heavy chains provides very specific binding site to
Active Immunity in animals Active immunity involves both the cell-mediated and humoral immunity as well as the innate immune system. Active immunity is induced in the host itself by the antigen, and lasts for a longer period of time. Types of active immunity Naturally acquired active immunity Naturally acquired active immunity occurs when an individual
Immunity in Animals Immunity is the ability of the body to resist the tissue damage by destroying the disease organisms or neutralizing their toxins. Types of immunity There are two types of immunity present in animals- Innate immunity and Acquired immunity. Innate immunity This type of immunity is present from birth. This type of immunity is
Plasma Cells in animals Plasma cells are white blood cells which produce large volumes of antibodies. They are transported by the blood plasma and the lymphatic system and originate from the bone marrow. They are otherwise known as plasma B cells , plasmocytes , and effector B cells. They are present in lymph nodes ,spleen
Monocytes of animals Monocytes of animals are the largest of WBCs, characterized by kidney or bean shaped nucleus. Monocytes are actively motile, pinocytic and also highly phagocytic, which may migrate into the tissue spaces and become macrophages. These cells are much more powerful phagocytes than neutrophils by their ability to engulf much large sized particles, necrotic tissues
Lymphocytes of Animals Lymphocytes cells are characterized by well defined centrally placed nucleus, surrounded by cytoplasm. According to the size and the ratio of nucleus to cytoplasm, these cells are further divided into 3 types- Small lymphocytes: These are small sized cells with a large notched nucleus. Medium lymphocytes: These are medium sized, which have notched nucleus surrounded
Basophils of Animals Basophils cells are found in the blood in lower concentration. They have irregular shaped nucleus and the granules are stained blue by the basic dye of Leishman’s stain. They originate in the bone marrow and have slight or no phagocytosis. Extravascularly, basophils enlarge and become tissue mast cells. Both basophils and mast cells
Eosinophils of animals Eosinophils of animals are large cells which contain large cytoplasmic granules that stain red or purple eosin stain. They have bilobed nucleus, connected by a thin filament. The cytoplasmic granules contain enzymes, which are rich in oxidases‚ and peroxidases. Eosinophils are produced from the bone marrow and are highly motile, but less
Neutrophils of animals Neutrophils of animals are produced in the bone marrow from the extravascular neutrophilic myelocytes. They are numerously found in the blood of most animals. The nucleus of mature cells is divided into lobes, usually five lobes and are stained blue or purple by Leishman’s stain. They have abundant and fine granular cytoplasm
