Chapter 20: Lymphatic and Immune System Flashcards
The ________ not an organ system, but a cell population that inhabits all organs and defends the body from agents of disease
Immune system
What are pathogens?
agents capable of producing disease
What are some examples of pathogens?
viruses, bacteria, and fungi
____________ in small intestine absorb dietary lipids
Lacteals
What do both lymphatic and immune systems do?
Maintain fluid balance
Protect body from infection and disease
________ is clear, colorless fluid, similar to plasma but much less protein
lymph
________ is the recovered fluid
lymph
________ transport the lymph
lymphatic vessels
____ are composed of aggregates of lymphocytes and macrophages that populate many organs in the body
lymphatic tissues
________ are defense cells are especially concentrated in these organs
Separated from surrounding organs by connective tissue capsules
Lymphatic organs
What are the 3 layers of the larger lymphatic vessels?
Tunica interna, media, externa
What layer of the lymphatic vessel has the endothelium and valves?
Tunica interna
What layer of the lymphatic vessel has elastic fibers, smooth muscle?
Tunica media
What is the thin outer layer of the lymphatic vessel?
Tunica externa
What are the cells of the lymphatic system?
Natural killer cells
T-cells
B-cells
Macrophages
Dendritic Cells
Reticular cells
What are the tissues of the lymphatic system?
Diffuse lymphatic tissue
Mucosa-associated lymphatic tissue (MALT)
____ cells attack foreign and infected host cells and are responsible for immune surveillance
natural killer (nk) cells
T lymphocytes develop in the ________ but mature in ______
Bone marrow
Thymus
What are the antigen presenting cells?
Macrophages, dendritic and reticular cells
What are the main APCs that develop from monocytes?
Macrophages
What does MALT stand for?
Mucosa-associated lymphatic tissue (MALT)
What kind of tissue is MALT?
Diffuse lymphatic tissue
____ are dense oval masses of lymphocytes and macrophages that congregate in response to pathogens
Lymphatic nodules
What are lymphatic nodules a constant feature of?
lymph nodes, tonsils, and appendix
Lymphatic organs are anatomically well-defined. They have ____________ that separates lymphatic tissue from neighboring tissues
connective tissue capsule
What are the primary lymphatic organs?
Red bone and thymus
What are the secondary lymphatic organs?
Lymph nodes, tonsils, and spleen
What systems is the thymus a member of?
endocrine, lymphatic, and immune systems
What does the thymus house?
Developing lymphocytes
What hormones does the thymus secrete?
thymopoietin, thymulin and thymosins
What age does the thymus begin involution?
14
Where are the cervical lymph nodes found?
In the neck
What kind of nodes are found in the armpit?
Axillary lymph nodes
Where are thoracic lymph nodes found?
In the thoracic (chest) cavity
What lymph nodes occur in posterior abdominopelvic wall?
Abdominal lymph nodes
What lymph nodes are found in the mesenteries, adjacent to the appendix and intestines?
Intestinal and mesenteric lymph nodes
Where are inguinal lymph nodes?
In the groin and receive lymph from the entire lower limb
What lymph nodes occur on the back of the knee?
Popliteal lymph nodes
What is the collective term for all lymph node diseases?
Lymphadenopathy
________ is the swollen, painful lymph node responding to foreign antigen
Lymphadenitis
What are common sites for metastatic cancer?
lymph nodes
________ are when cancerous cells break free from original tumor, travel to other sites in the body, and establish new tumors
Metastasis
How many sets of tonsils are there?
3
What are tonsils?
patches of lymphatic tissue located at the entrance to the pharynx
What do tonsils guard against?
ingested or inhaled pathogens
What are the 3 main sets of tonsils?
palatine, lingual, pharyngeal (adenoids)
The ____ is the largest lymphatic organ
Spleen
What is the spleen also known as?
erythrocyte graveyard”
What are some functions of the spleen?
Blood production
Blood reservoir
RBC disposal
Immune reactions
What are the 2 categories of lymphatic defenses?
Innate (nonspecific) immunity
Adaptive (specific) immunity
What defense requires no prior exposure?
innate (nonspecific) immunity
____ results from prior exposure
adaptive (specific) immunity-
how many lines of defenses against pathogens?
Three
What are defensins?
peptides, from neutrophils attack microbes by creating holes in their membranes
Where is lysozyme found?
In mucous, tears and saliva
What are the phagocytic cells?
the 5 types of leukocytes
What histamine and what does it do?
a vasodilator that increases blood flow to infected area
What is heparin and what does it do?
an anticoagulant that prevents immobilization of phagocytes
What are the 2 families of microbial proteins?
Interferons and complement system
____ are proteins that alert neighboring cells and prevents them from becoming infected
Interferons
What do T cells attack?
Foreign cells and diseased host cells
What the 3 major classes of T cells?
Cytotoxic T cells (Tc cells)
Helper T cells: (T_H)
Memory T cells: (T_M)
____ cells carry out attack of enemy cells
Cytotoxic T cells
____ cells help promote Tc cell and B cell action and nonspecific (innate) defense mechanisms
helper T cells
____ cells descend from the (TC) and are responsible for memory in cellular immunity
Memory cells
What is there a lack of in severe combined immunodefiency?
Hereditary lack of T and B cells
What are the most common means of transmission?
Sexual intercourse (vaginal, anal, oral)
Contaminated blood products
Contaminated needles
What causes AIDs?
Infection with the human immunodeficiency virus (HIV)
What are the types of antibodies?
IgA: mucus, saliva, tears, milk (passive immunity to newborns), intestinal secretions, prevents adherence to epithelia
IgD: thought to function in B cells activitation by antigen
IgE: stimulates release of histamines, attracts eosinophils; immediate hypersensitivity reactions (inflammation & allergy)
IgG: 80% circulating, crosses placenta to fetus, 2 “secondary” immune response, complement fixation
IgM: 10% in plasma, 1 “primary” immune response, agglutination, complement fixation
What is the cisterna chyli?
A sac-like structure in the lymphatic system that serves as a collection point for lymph fluid from the lower half of the body. In the abdominal region
