Vocab Flashcards
Lymph contains solutes from two sources
A) substances in plasma: ions, gas, nutrients, proteins
B) substances derived from cells: hormones, enzymes, waste
Lymph
3L of fluid that enter lymphatic capillaries.
Lacteals
Lymphatic system absorbs lipids from digestive tract. In small intestine
Chyle
Lipids enter lacteals then pass into venous circulation. Lymph called chyle.
Lymphatic system includes
Lymph, lymphatic vessels, lymphatic tissue, nodules, nodes, tonsils, spleen, thymus
Lymphatic capillaries
Begin as small, dead-end tubes
Lymphatic vessels
Resemble small veins.
Three major mechanisms for moving lymph
1) contraction of lymphatic vessels
2) contraction of skeletal muscles
3) thoracic pressure changes
Lymph nodes
Round, oval, bean shaped bodies. Filter lymph!!!!
Flow of lymph
Capillaries, vessels, nodes, trunk, duct
Lymphatic trunk
Vessels converge to form larger vessel (trunks) that drain major portion of body
Jugular trunk
Drains head and neck
Subclavian trunk
Drains upper limbs, thoracic wall, mammary glands
Bronchomediastinal trunks
Drain thoracic organs and deep thoracic wall
Intestinal trunks
Drain abdominal organs
Lumbar trunks
Drain lower limbs, pelicans and abdominal walls, ovaries, tested, kidneys, adrenal glands
Lymphatic ducts
Lymphatic trunks connect to form ducts
Right lymphatic duct
20% of people: three trunks join to form a short duct that joins right thoracic vein
Thoracic duct
Largest. Drains lymph from right side inferior to thorax and entire left side of body
Cisternae chyli
In a some people, lymphatic trunks form a sac
Two types of lymphocytes
B cells and T cells
Reticular fibers
Makes up lymphatic tissue. Fine collagen fibers. Lymphocytes attach and filter lymph
Nonencapsulated
Lymphatic tissue that is not surrounded by a connective tissue capsule
Mucosa associated lymphoid tissue
MALT
Aggregations of nonencapsulated lymphatic tissue. Found in and beneath mucous membranes lining digestive, respiratory urinary and reproductive tracts.
Examples of MALT
Diffuse lymphatic tissue, nodules, tonsils.
Lymphatic organs with a capsule
Nodes, spleen, thymus
Diffuse lymphatic tissue
Contains dispersed lymphocytes, macrophages. No clear boundary, blends in with surrounding tissues. Within nodes and spleen
Lymphatic nodules
Denser arrangements of lymphatic tissue. Numerous in loose connective tissue of digestive, respiratory, urinary and reproductive
Peyer patches
Nodules in distal half of small intestine and appendix
Lymphatic follicles
Lymphatic nodules found in nodes and spleen
Tonsils
Large groups of nodules and diffuse lymphatic tissue
Three groups of tonsils.
Palatine, pharyngeal, lingual
Palatine tonsils
Usually referred to. Oval lymphatic masses on each side of throat.
Pharyngeal tonsil
Near junction of nasal cavity and pharynx (when enlarged, called adenoid)
Lingual tonsil
Posterior surface of tongue
Lymph nodes
Small, round, bean shaped. Distributed along vessel. Filter lymph
Superficial lymph nodes,
Deep lymph nodes
Subcutaneous tissue beneath the skin, deep are everywhere else
Capsule
Dense connective tissue that surrounds each lymph node
Trabeculae
Extensions of the capsule, form delicate internal skeleton of lymph node
Lymphatic sinuses
Reticular fibers extend across open spaces
Medulla
Inner layer. Medullary cords
Afferent lymphatic vessels
Carry lymph to lymph nodes
Efferent lymphatic vessels
Carry lymph away from nodes
Germinal centers
Areas of rapid lymphocyte division. Especially in lymphatic nodules if cortex
Spleen
Clenched fist, left, superior part of abdominal cavity. FILTERS BLOOD
White pulp
Lymphatic tissue surrounding the arteries within the spleen. ANTIBODIES
Red pulp
Associated with veins. MONOCYTE storage
Periarterial lymphatic sheath
Composed of diffuse lymphatic tissue surrounding arteries and arterioles extending to lymphatic nodules
Splenic cords
Network of reticular cells that produce reticular fibers
Venous sinuses
Enlarged capillaries between the splenic cords
Splenic vein
Venous sinuses and trabecular veins unite and leave spleen
Splenectomy
Removal of the spleen
Thymus
Bilobed gland. Superior mediastinum.
Lobules
Trabeculae of thymus divide it into lobules
Thymic corpuscles
Function in development of regulatory T cells
Regulatory T cells
Suppress body’s immune response and protect against autoimmune diseases.
Immunity
Ability to resist damage from foreign substances
Innate immunity
Nonspecific resistance. Body recognizes and destroys certain foreign substances, but the response to them is the same each time the body is exposed.
Adaptive immunity
Specific immunity. Response is faster and stronger each time foreign substance is encountered
Specificity
Ability of adaptive immunity to recognize a particular substance
Memory
Ability of adaptive immunity to remember previous encounters of a substance
Main components of innate immunity
1) physical barriers
2) chemical mediators
3) phagocytosis and chemicals
Chemical mediators
Molecules responsible for many aspects of innate immunity.
Cytokines
Proteins or peptides secreted by cells that bind to receptors on cell surfaces, stimulating a response. Interferons, interleukins, lymphokines
Complement
Group of 20 proteins that make up 10% of plasma. Normally inactive until complement cascade.
Surface chemicals
Lysozymes (tears, saliva, nasal, sweat) lyse cells. Acid (sebum, hydrochloride acid) prevent growth or kill microorganisms
Histamine
Released from mast cells, basophils, platelets. Causes vasodilalation and permeability
Kinins
Derived from plasma proteins. Vasodilalation, permeability, stimulate pain receptors, attract neutrophils
Interferons
Proteins from most cells, interfere with virus production and infection. Perhaps some forms of cancer
Prostaglandins
Group of lipids, cause smooth muscle relaxation and vasodilalation, permeability and pain receptors
Leukotrienes
From mast cells and basophils. Cause prolonged smooth muscle contraction (lung bronchioles) permeability, neutrophils, eosinophils
Pyrogens
Stimulate fever production
Complement cascade
Series of reactions where each component activates the next
Alternative pathway
Part of innate immunity. Complement protein C3 becomes active (by proteins in cell surfaces)
Classical pathway
Adaptive immunity.
Membrane attack complex
Produces a channel through the plasma membrane . Na and water enter cell and cause it to lyse
Optimization
Complement proteins attach to the surface of bacterial cells and stimulate macrophages to phagocytize
Interferons - how?
Bind to the surface of neighboring cells and stimulate them to produce antiviral proteins. Innate.
Neutrophil
Phagocytosis and inflammation.
Monocyte
Leaves blood and enters tissue to become a macrophage
Macrophage
Most effective phagocyte. Later stage of infection and tissue repair.
Basophils
Motile, enters tissues, releases inflammatory chemicals
Mast cells
Nonmotile cell in connective tissue that promotes inflammation
Eosinophils
Parasitic infection, asthma and allergies
Natural killer cell
Lyse tumor and virus infected cells innate
B cell
After activation, differentiates to become plasma cell or memory B cell
Plasma cell
Adaptive.
Produces antibodies
Memory B cell
Quick and effective response to an antigen after previous encounter. Responsible for adaptive immunity
Cytotoxic T cell
Responsible for destroying cells. By lysis or by producing cytokines
Helper T cell
Activates B cells and cytotoxic T cells
Regulatory T cell
Inhibits B cells, helper T cells and cytotoxic T cells
Memory T cell
Quick and effective response from previous encounter. Responsible for adaptive immunity.
Dendritic cell
Processes antigen and is involved in activation if B cells and T cells
Antibody-mediated immunity
Antibodies found in interstitial fluid and lymph. B cells give rise to cells that produce antibodies.
Cell mediated immunity
Cytotoxic T cells are responsible for cell meditated immunity.
Helped T cells and regulatory T cells
Promote or inhibit both antibody-mediated and cell-mediated immunity
Positive selection
Survival of pre-B and pre-t cells that are capable of an immune response
Clones
B cells and T cells that can respond to antigens are composed of small groups of identical lymphocytes
Negative selection
Eliminates or suppresses clones acting against self antigens. Mostly during prenatal development
Primary lymphatic organs
Red bone marrow, thymus. Where lymphocytes mature
Secondary lymphatic organs and tissues
Lymphocytes interact with each other and antigens to produce an immune response. Lymphatic tissue, nodules, tonsils, nodes, spleen
Antigenic determinants
Epitopes. Specific regions of a given antigen recognized by a lymphocytes.
Antigen receptors
Identical protein on a lymphocyte that bind to a specific determinant in an antigen
Major histocompatibility complex molecules MHC
Glycoproteins found on plasma membranes of most of the body’s cells
MHC class I molecules
On nucleated cells: they display antigens produced inside the cell on the cells surface
MHC class II molecules
Found on antigen presenting cells. B cells, macrophages, monocytes, destructive cells
Constimulation
Accomplished by cytokines released from cells and by molecules attached to the surface of cells
Lymphokines
Cytokines produced by lymphocytes
Tolerance
State of unresponsiveness of lymphocytes to a specific antigen
Opsonins
Substances that make an antigen more susceptible to phagocytosis
Plasma cells
Produce antibodies
Cell mediated immunity is most effective against
Intercellular microorganisms through the action of cytotoxic T cells. Involves delayed hypersensitivity reactions and control tumors
Cytotoxic T cells effects
Lyse cells and produce cytokines.
Perforin
Major method of lysis. Forms a channel in target membrane to allow water inside
Immunotherapy
Altering immune system function or directly attacking harmful cells
Antiserum
Plasma minus clotting factors. Passive artificial immunity
