Ch. 22 Flashcards
The lymphatic system has what 3 main functions?
- Fluid balance
- Lipid absorption
- Defense
Lymph
The fluid that leaves the blood. It contains solutes derived from substances in the plasma, such as ions, nutrients, gases, and some proteins, also hormones, enzymes and waste products
Lacteals?
Chyle?
Lymphatic vessels located in the lining of the digestive tract
*absorbs lipids and other substances from the digestive tract
Chyle is lymph passing through lymphatic vessels and it appears white due to lipid content
The lympathatic system includes?
Lymph, lymphatic vessels, lymphatic tissues, lymphatic nodules, lymph nodes, tonsils, spleen, thymus
Lymphatic capillaries
Tiny vessels that collect and filter fluid from your bodies cells and tissues
Help maintain blood pressure, volume and prevent build up
Lymphatic vessels
lymphatic capillaries join to form larger lymphatic vessels which resemble small veins
have 1 way valves
Lymph moves through the lymphatic vessels by what 3 mechanisms?
- Contraction of lymphatic vessels - smooth muscles contract via pacemaker cells
- Contraction of skeletal muscles
3. Thoracic pressure changes - during inspiration & exoiration
Lymph nodes
round, oval or bean-shaped bodies distributed along various lymphatic vessels
-filter lymph
Lymphatic trunks
lymphatic vessels converge to form lymphatic trunks which drains lymph from a major portion of the body
What are the 5 main lymphatic trunks
- Jugular trunk - drain lymph from the head and neck
- Subclavian trunk - drain lymph from the upper limbs, superficial thoracic wall and mammary glands
- Bronchomediastinal trunk- drain lymph from the thoracic organs and deep thoracic wall
4. Intestinal trunks - drain lymph from the abdominal organs such as intestines, stomach, pancreas, spleen, liver
5. Lumbar trunk - drain lymph from the lower limbs, pelvic and abdominal walls, pelvic organs, ovaries or testes, kidneys and adrenal glands
Lymphatic ducts
larger vessles where lymphatic trunks join, which then connect to large veins
Right lymphatic duct
Thoracic duct
Right lymphatic duct - drains from right side of head, upper right limb and right thorax
Thoracic duct - largest lymph vessel, drains from entire left side of body and right side inferior to the thorax
Cisterna chyli
a sac formed by lymphatic trunks
Lymphatic tissue consists of
lymphocytes, macrophages, dendritic cells, reticular cells, reticular fibers
Mucosa-associated lymphoid tissue (MALT)?
aggregates of nonencapsulated lymphatic tissue found in and beneath the mucous membranes lining the digestive, respiratory, urinary and reproductive tracts
lymphatic tissue here is well-positioned to intercept microorganisms as they enter the body
Diffuse lymphatic tissue
contains dispersed lymphocytes, macrophages and other cells
Has no clear boundary and blends with surrounding tissues
located deep to mucous membranes, around lymphatic nodules and within lymph nodes and spleen
Lymphatic nodules
denser arrangements of lymphatic tissue organized into compact spherical structures
Numerous in loose connective tissue of digestive, respiratory, urinary and reproductive systems
Peyer patches
aggregations of lymphatic nodules in the distal half of small intestine
Tonsils
large groups of lymphatic nodules that diffuse lymphatic tissue
located deep to mucous membranes in the pharynx
What are the 3 types of tonsils?
Palatine tonsils - relatively large, on each side of oral cavity and the pharyns
Pharyngeal tonsils - collection of closely aggregated lymphatic nodules near nasal cavity and pharynx
lingual tonsils - on posterior surface of tounge
What are lymph nodes?
What are the 2 types of lymph nodes?
what surrounded each lymph node?
Lymph nodes are small round structures that filter the lymph
Superificial - in subcutaneous tissue
Deep - every where else
a capsule with trabeculae (internal skeleton)
what are afferent lymphatic vessels?
What are efferent lymphatic vessels?
Afferent carry lymph to the lymph nodes
Efferent lymphatic vessels carry lymph away from lymph nodes
Spleen - function
Size?
Location?
White pulp?
Red pulp?
The organ that destroys defective red blood cells, detecting and responding to foreign substances in the blood, acting as a blood reservoir
Size of a clenched fist
located in the superior part of the abdominal cavity
White pulp is lymphatic tissue surrounding the arteries within the spleen
Red pulp is associated with veins within the spleen
What are the spleens main 3 function and how does it carry those functions out?
- Destorying defective red blood cells - Defective red blood cells lose their ability to bend and fold so they rupture as they pass through and macrophages phagocytes them
- Detect foreign substances - Foreign substances passing through the spleen stimulate an immune response from the lymphocytes
- Act as blood reservoir - Splenic cords are a limited reservoir
splenectomy
removal of the spleen
Thymus - location?
Function?
Thymic corpusles?
Bilobed gland located in superior mediastinum - has compartments of lymphocytes
Function - developement of regulatory T cells
Thymic corpusels function in the development of regulatory T cells which suppress the body immune response and protect against auto immune diseases
Define immunity
Immunity is the ability to resist damage from foreign substances such as microorganisms; harmful chemicals and internal threats
What is innate immunity?
What is adaptive immunity?
Innate immunity the body recognizes and destroys certain foreign substances, but the response to them is the same each time
Adaptive immunity the body recognizes and destroys certain foreign substances but the response to them is faster and stronger each time
What is specificity?
Which immunity is it related to
What are the 3 main components of innate immunity?
- Physical barrier - prevent entry of disease by skin, muscous membrane. (tears, saliva, urine all wash away microorganisms)
- Chemical mediators - lysosomes, histamine, interferons, complements
- Phagocytosis - neutrophils, macrophages, basophils, mast cells, eosinophils
What is a complement protein?
a group of about 20 proteins that protect the body by destroying abnormal cells or enchanting other components of immunity
* Make up approx 10% of the globulin part of plasma proteins
*can also cause inflammation, act as chemical signals attracting other cells to sites of injury or infection
What is a membrane attack complex (MAC)?
produces a channel through a cells plasma membrane that ultimately destroys the cell
What is opsonization?
complement proteins can attach to surface of bacterial cells and stimulate macrophages to phagocytize bacteria
What are interferons
Proteins that protect the body against viral infections and perhaps some form of cancer
White blood cells
are produced where?
attracted to chemical signals called?
most important cellular components in the immune system
produced in the red bone marrow and lymphatic tissue and released into the blood
chemoctactic factors
What is an inflammatory response?
a complex sequence of events involving many of the chemical mediators and cells of innate immunity
Local inflammation
Systemic inflammation
an inflammatory response confined to a specific area of the body
systemic inflammation is an inflammatory response that occurs in many parts of the body
What are substances that stimulate adaptive immunity are….
what are the 2 types of antigens?
Antigens
Foreign antigens and self antigens
What are foreign antigens?
What are Self antigens?
Foreign antigens are not produced by the body but are introduced from outside
Self antigens are molecules that the body produces to stimulate an adaptive immune system response
What is an allergic reaction?
What is autoimmune disease?
Allergic reaction is an overreaction of the immune system
Autoimmune disease is when self antigens stimulate unwanted tissue damage
What is antibody mediated immunity?
What is cell mediated immunity?
Antibody-mediated immunity involves proteins called antibodies which are found in extracellular fluids
Cell-mediated immunity involves actions of T cells
What are cytotoxic T cells?
What are helper T cells?
What are regulatory T cells?
Cytotxic T cells are responsible for producing the effects of cell-mediated immunity
Helper T cells & regulatory T cells promote or inhibit the activities of both antibody-mediated immunity and cell-mediated immunity
The thymus releases what hormone which stimulates T cell maturation?
Thymosin
What is the positive selection process?
What is the negative selection process?
What is a clone?
Positive selection process involves survival of pre-B and Pre-T cells that are capable of an immune response
Negative selection process eliminates or suppresses clones acting against self antigens
Clones are small groups of identical lymphocytes which respond to same anitgen
What are the primary lymphatic organs?
what are secondary lymphatic organs?
Primary lymphatic organs are red bone marrow and thymus
Secondary lymphatic organs are lymphatic tissue, lymphatic nodules, tonsils, lymph nodes, spleen
Antigenic determinants or epitopes?
The lymphocytes of a given clone have on their surface identical proteins called?
Specific regions of the antigen that lymphocytes interact with
Antigen receptors
T cell antigen receptor consists of..
B cell antigen receptors consist of..
2 polypeptide chains subdivided into variable region and constant region
4 polypeptide chains with 2 identical variable regions
What is major histocompatibility complex molecules (MHC)?
What are the 2 classes of MHC?
are glycoproteins found on the plasma membranes of most of the body cells. Each MHC molecule has a variable region that can bind antigens found inside the cell
MHC class 1 molecules and MHC class II molecules
MHC class 1 molecules are found on….Cells? and function how?
MHC class II molecules are found on?
MHC class 1 molecules are found on nucleated cells and display antigens produced inside the cell on the cells surface
Antigen presenting cells (B cells, macrophages, monocytes, dendritic cells) they take foreign antigens by endocytosis where its broken down into fragments to form processed antigens which produce a stimulation for more immune cells
What is the process of lymphocyte proliferation>
- Proliferation of helper T cells
- Proliferation and activation of B cells or cytotoxic T cells
What is tolerance?
a state of unresponsiveness of lymphocytes to a specific anitgen
What are 3 ways tolerance can be induced?
- deletion of self-reactive lymphocytes
- Prevention of the activation of lymphocytes
- activation of regulatory T cells
What is the variable region?
What is the constant region?
Variable region is the part of the antibody that combines with the antigenic determinants of the antigen
The constant region is the rest of the antibody which is responsible for the activities of the antibodies
What are the 3 effects of antibodies?
- Stimulates inflammation; attracts neutrophils, monocytes, macrophages and eosinophils to sites of infection and kills by lysis
- Inflammation; release chemicals via exocytosis; produces swelling and increased mucous
- act as opsonins by connecting a antigen to a macrophage then it gets phagocytized
What is a primary response?
what is a secondary response?
primary response is the first exposure of a B cell to an antigen. It includes a series of cell divisions, cell differentiation and antibody production
Secondary response or memory response occurs when the immune system is exposed to an antigen against which it has already produced a primary response
