RAT 9 Flashcards
what two systems are covered in this chapter? why are they covered together?
- lymphatic and immune system
- they function together in immunity
what system is technically not a system? why?
immune system because it doesn’t contain organs or tissues of its own instead it consist of cells and proteins
what are the main components of the lymphatic system?
- lymphatic vessels
- lymphatic tissue and lymphatic organs
what are the functions of the lymphatic system?
- regulation of interstitial fluid volume
- absorption of dietary fats
- immune functions
what is lymph?
interstitial fluid that has exited the extracellular space and extended and entered the lymphatic vessels
what is a lymph collecting vessel?
vessels that collects lymph
what is a lymphatic trunk?
large vessel made up of lymph collecting vessels
what do the intestinal and lumbar trunks drain into?
cisterna chyli
what is drained by the thoracic duct?
all of the lower body and the left side of the upper body
what is drained by the right lymphatic duct?
the right side of the upper body
what does the thoracic duct drain into?
junction of the left internal jugular and left subclavian veins
what does the right lymphatic duct drain into?
junction of the right internal jugular and right subclavian veins
what structure/mechanisms aid in the flow of lymph?
- lymphatic valves: prevent backward flow of lymph
- found between contracting muscles, where contracting muscles massage lymph up toward the heart
- flows through the vessel driven in part by contractions of smooth muscle found in the walls of lymph-collecting vessels
describe the structure of lymphatic capillaries
weblike networks that surround blood capillary beds
what is a lacteal?
specialized lymphatic capillary that collects fat in the small intestine
name the predominant type of tissue in the lymphatic system.
reticular tissue
what is another name for reticular tissue?
lymphoid tissue
what cells are found in lymphoid tissue?
- lymphocytes (B & T)
- phagocytes (macrophages and dendritic cells)
- reticular cells
what is MALT?
- mucosa-associated lymphatic tissue
- loosely organized clusters of lymphoid tissue
where is MALT found?
scattered throughout the gastrointestinal tract, the respiratory passage, and the genitourinary tract
what are lymphoid follicles/lymphoid nodules?
roughly spherical clusters that consist primarily of B cells
name the three locations where lymphoid follicles are found.
- tonsils
- peyer’s patches
- appendix
where are tonsils located?
around the oral and nasal cavities
what are the deep indentions in the tonsils called?
tonsillar crypts
what is the function of tonsillar crypts?
trap bacteria and debris
where are peyer’s patches located?
in the last portion of the small intestine (the ileum)
what is the function of peyer’s patches?
defend against any bacteria that have escaped from the large intestine
where is the appendix located?
located off the large intestine
what is the function of the appendix?
defends against bacteria in the large intestine, specifically those that could be pathogenic
name some locations where lymph nodes are clustered together.
- axillary lymph nodes
- cervical lymph nodes
- inguinal lymph nodes
- mesentric lymph nodes
describe the structure of the lymph node
- small, vaguely bean-shaped clusters of lymphatic tissue
- interior divided into 2 regions: cortex (outer) and medulla (inner)
describe the basic process by which a lymph node filters lymph
- flow into the node through afferent lymphatic vessels into subcapsular sinus into cortical sinuses into medullary into drains out through efferent lymphatic vessels
what are “swollen glands”?
when a lymph node has swollen due to a pathogen entering and B cells being activated
why is the term “swollen glands” technically incorrect?
lymph nodes are not glands and they secrete no products
what organ protects us from pathogens in the blood?
spleen
what is the largest lymphatic organ?
spleen
describe the size and shape of the spleen.
purple-brownish organ about the size of a large bar of soap
what are the two histological regions of the spleen?
- red pulp
- white pulp
what cells are found in red pulp?
macrophages, erythrocytes
what cells are found in white pulp?
filters pathogens from blood and leukocytes
where is white pulp located?
surrounds branches of the splenic artery
what is the function of white pulp?
filters pathogens from the blood
what is the primary function of the thymus?
generate a population of functional T cells capable of protecting the body from pathogens
what happens to the thymus as we age?
- atrophy, thymic tissue is gradually replaced with fat
- T cell production drops
what are the three lines of defense against pathogens?
- cutaneous and mucous membranes that act as surface barriers to block the entry of pathogens into the body
- responses of the cells and proteins that make up innate immunity
- response of the cells and proteins of adaptive immunity
what is innate or nonspecific immunity?
responds to all pathogens or classes of pathogen in the same way
what is adaptive or specific immunity?
respond to unique markers (antigens)
what is an antigen?
unique markers that distinguish cells
what are the two “arms” of the adaptive immune system?
- cell-mediated immunity
- antibody-mediated immunity
what cells carry out cell-mediated immunity?
2 types of T cells
what cells carry out antibody-mediated immunity?
B cells and proteins that produce antibodies
which is faster, adaptive immunity or innate immunity?
innate immunity
does adaptive immunity or innate immunity have “memory”?
adaptive immunity
what does “memory” mean?
exposure to a specific antigen is “remembered” by lymphocytes and antibodies
how is skin an effect skin barrier?
- covers nearly every external surface of the body
- relatively resistant to mechanical stresses (due to keratin)
what are mucous membranes?
sheet of epithelium and the underlying basement membrane that produces mucus
where are mucous membranes located?
lines internal hallow organs that open to the outside
how are the effect surface barriers of mucous membranes?
semi-effective because its thinner and lacks keratin
describe the main types of cells and proteins of the immune system
- agranulocytes
- granulocytes
- phagocytes
- natural killer cells
- antibodies
- complement system
- cytokines
explain how the lymphatic system and immune system work together.
- lymphoid organs and tissues provide a residence for cells of the immune system
- lymphoid organs and tissues trap pathogens for the immune system
- lymphoid organs activate cells of the immune system
list the components of the respiratory system
- nose and nasal cavity
- pharynx (throat)
- larynx
- trachea
- brachial tree (bronchi, bronchioles)
which components are considered part of the upper respiratory tract?
- nose and nasal cavity
- pharynx
- larynx
which components are considered part of the lower respiratory tract?
- trachea
- bronchial tree (bronchi and bronchioles)
- alveoli
what are the two functional divisions of the respiratory system?
- conducting zone
- respiratory zone
what are the functions of the conducting zone?
conduits through which air travels on its way in and out of the body as its inspired and expired
which structures does the conducting zone include?
- nose
- nasal cavity
- pharynx
- larynx
- trachea
- bronchi
- bronchioles
what is the primary function of the respiratory zone?
where gases are exhanged
which structures does the respiratory zone include?
structures that contain alveoli
define respiration
process that provides the body’s cells with oxygen and removes the waste product carbon dioxide
list the four parts of respiration
- pulmonary ventilation
- pulmonary gas exchange
- gas transport in the blood
- tissue gas exchange
define ventilation
movement of air in and out of the lungs
besides respiration, what are some other functions of the respiratory system?
- producing speech
- detecting odors
- helping to expel contents of the abdominopelvic cavity
- maintaining acid-base homeostasis
- assisting in production of angiotensin-II
