In which organ of human body are the lymphocyte cells formed

Function What do white blood cells do? White blood cells protect your body against infection. As your white blood cells travel through your bloodstream and tissues, they locate the site of an infection and act as an army general to notify other white blood cells of their location to help defend your body from an attack of an unknown organism. Once your white blood cell army arrives, they fight the invader by producing antibody proteins to attach to the organism and destroy it. Anatomy Where are white blood cells located? Your white blood cells are in your bloodstream and travel through blood vessel walls and tissues to locate the site of an infection. What do white blood cells look like? Contrary to their name, white blood cells are colorless but can appear as a very light purple to pink color when examined under a microscope and colored with dye. These extremely tiny cells have a round shape with a distinct center membrane (nucleus). How big are white blood cells? You can only see white blood cells under a microscope, as they are extremely small. How many white blood cells are in my body? White blood cells account for 1% of your blood. There are more red blood cells in your body than white blood cells. How are white blood cells formed? White blood cell formation occurs in the soft tissue inside of your bones (bone marrow). Two types of white blood cells (lymphocytes) grow in the thymus gland (T cells) and lymph nodes and spleen (B cells). What are white blood cells made o...

Term Meaning Pathogen A disease-causing organism, including bacteria, Antigen Molecule that stimulates an immune response Innate immune system Non-specific immune system Adaptive immune system Antigen-specific immune system Antibody Specialized Y-shaped protein that tags antigens for destruction B cells White blood cells that produce antibodies and aid in immunological memory T cells White blood cells specialized to assist B cells (helper T) and others directly kills infected cells (killer T) Humoral immunity Adaptive immune defense depending on the action of antibodies Cell-mediated Immunity Adaptive immune defense in which foreign cells are destroyed by T cells Virus Nonliving particle containing protein and DNA/RNA that can infect a living cell Vaccine A killed or weakened form of a pathogen that produces immunity when injected into the body An inflammatory response begins when a pathogen stimulates an increase in blood flow to the infected area. Blood vessels in that area expand, and white blood cells leak from the vessels to invade the infected tissue. These white blood cells, called phagocytes engulf and destroy bacteria. The area often becomes red, swollen, and painful during an inflammatory response. Specific immune responses are triggered by antigens. Antigens are usually found on the surface of pathogens and are unique to that particular pathogen. The immune system responds to antigens by producing cells that directly attack the pathogen, or by producing special ...

Lymphocytes move around your body through the lymphatic system, which is part of the circulatory system. Lymph vessels carry clear fluid, including lymphocytes and other white blood cells, throughout your body to fight infection. Although there's some evidence that one type of lymphocyte may attack and destroy the infectious agent directly, for the most part lymphocytes leave that task to other types of white blood cells, including phagocytes. (Phagocytes work by actually swallowing and absorbing invaders that your body views as a threat, such as bacteria and small particles.) The "T" in T cell stands for thymus, the small gland in your chest where T cells go to mature after they're manufactured by your bone marrow, and before they're sent out to patrol your body. When a lymphocyte spots a cell that's been infected with bacteria or a virus, the lymphocyte will proceed to kill the cell. It also will actually remember the infectious agent, so it can act faster the next time it encounters the same infectious problem. This enables your immune system to identify and fight repeat infections more quickly. What Are B Cell Lymphocytes? B cell lymphocytes don't attack and kill cells, viruses or bacteria themselves. Instead, they manufacture proteins called antibodies that actually stick to the surface of invaders, disabling those invaders and spotlighting them for clean up by other parts of your immune system. The "B" in B cell lymphocytes stands for the bursa of Fabricius, a specia...

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Lymphocytes are a type of white blood cell. They help your body’s immune system fight cancer and foreign viruses and bacteria. Your lymphocyte count can be taken during a normal blood test at your healthcare provider’s office. Lymphocyte levels vary depending on your age, race, sex, altitude and lifestyle. Overview What are lymphocytes? Lymphocytes are a type of white blood cell. They play an important role in your • T lymphocytes (T cells): T cells control your body’s immune system response and directly attack and kill infected cells and tumor cells. • B lymphocytes (B cells): B cells make antibodies. Antibodies are proteins that target viruses, bacteria and other foreign invaders. Function What do lymphocytes do? Lymphocytes help your body’s immune system fight cancer and foreign viruses and bacteria (antigens). Lymphocytes help your immune system remember every antigen it comes in contact with. After an encounter, some lymphocytes turn into memory cells. When memory cells run into an antigen again, they recognize it and quickly respond. This is why you don’t get infections like How do T cells and B cells work? Your T cells and B cells work together. They each have different roles in your immune system. Your T cells help kill infected cells and control your body’s • Cytotoxic (killer) T cells: Cytotoxic T cells attach to antigens on infected or abnormal cells. Then, they kill the infected cells by making holes in their cell membranes and inserting enzymes into the cells....

Q. In which organ of the human body are the lymphocyte cells formed? Answer: [B] Long bone Notes: Lymphocytes are the cells that determine the specificity of the immune response to infectious microorganisms and other foreign substances. In humans lymphocytes make up 25 to 33% of the total number of leukocytes. They are found in central lymphoid organs and tissues such as the spleen, tonsils and lymph nodes and large bones. 3

The Human Body The most diffuse lymphoid tissue is found in the loose connective-tissue spaces beneath most wet Several types of cells are included in the lymphoid system—for example, reticular cells and white blood cells such as macrophages and The most common cell type in the lymphoid tissue is the