lymphatic system Flashcards
(110 cards)
1
Q
what does the lymphatic system do
A
returns extracellular fluid back to the cardiovascular system, provides immunity and aids in the digestion of fats
2
Q
what helps fight against infectious agents
A
masses of lymphocytes found in lymph nodes
3
Q
lymphatic capillaries
A
microscopic close ended tubes that extend into interstital spaces and recieve tissue through thin wall s
4
Q
lymphatic vessels are formed by the merging of what
A
lymphatic capillaries
5
Q
do lymph vessels have valves
A
yes
6
Q
what do larger lymphatic vessels merge into
A
lymphatic nodes which merge into lymphatic trunks
7
Q
lymphatic trunks do what
A
drain lymph from larger body regions
8
Q
the two collecting ducts that trunks lead to
A
thoracic and right lymphatic duct
9
Q
where do collecting ducts drain into
A
subclavian veins
10
Q
where does tissue fluid originate
A
plasma
11
Q
what is tissue fluid made of
A
water and dissolved substances that have passed through the blood capillary wall
12
Q
tissue fluid generally lacks what
A
large proteins
13
Q
what happens as the concentration of tissue fluid increases
A
colliod osmotic pressure increases
14
Q
how does fluid become lymph
A
increasing hydrostatic pressure in interstitial spaces forces some tissue fluid into lymphatic capillaries
15
Q
what does lymph formation prevent
A
edema
16
Q
what is true about the flow of lymph and hydrostatic pressure (HP)
A
it s under low HP and may not flow readily without external aid
17
Q
what moves lymph
A
contractions of skeletal muscle, smooth muscle in the walls of large lymphatic trunks, and the low pressure in the thorax created by breathing
18
Q
conditions affecting the flow of lymph results in what
A
edema
19
Q
lymphatic capillaries in the small intestine do what
A
absorb and transport lipids
20
Q
lymph returns what into the bloodstream
A
small protein molecules and fluid
21
Q
lymph transports what to the lymph nodes
A
foreign particles
22
Q
MALT
A
mucosa-associated lymphoid tissue
22
Q
what is MALT associated with
A
digestive, respiratory, urinary, and reproductive tracts
23
Q
what are the lymphatic organs
A
lymph nodes, thymus, and spleen
24
typical shape of lymph nodes
bean shaped
25
lymph nodes are enclosed in what
CT that extends into the nodes
26
lymph nodes subdivide into what
nodules
27
what do lymph nodes do
filter potentially harmful foreign particles from the lymph before it is returned to the bloodstream
27
nodules contain what
masses of lymphocytes and macrophages and spaces through which lymph flows
28
where are lymph nodes located, and in what regions/cavities
in groups or chains along larger lymphatic vessels
cervical region
axillary region
supratrochlear region
inguinal region
pelvic cavity
thoracic cavity
abdominal cavity
29
what does the thymus do after puberty
slowly shrinks
29
what do lymph nodes contain
lymphocytes that act against foreign particles and macrophages that remove foreign particles
30
what is the thymus
a soft bilobed organ within the mediastinum
31
what do lobules contain
lymphocytes
31
what is the thymus composed of and subdivided into
composed of lymphatic tissue and subdivided into lobules
32
what leaves the thymus and provides immunity
T lymphocytes
33
what does the thymus secrete
thymosins
34
what do thymosins stimulate
maturation of T lymphocytes
35
where is the spleen
ULQ of abd cavity
35
what are the spaces in splenic lobules filled with
blood
36
what does the spleen resemble
a large lymph node encapsulated and subdivided into lobules by CT
37
what does the spleen do
filter foreign particles and damaged red blood cells from the blood
38
what does the spleen contain
macrophages and lymphocytes
38
types of immunity
innate and adaptive
39
what may cause an infection
the presence and reproduction of a pathogen
40
examples of mechanical barriers
hair, sweat, tears, saliva, urine
40
what are pathogens
bacteria, protozoa, fungi, and viruses
41
what is innate immunity
nonspecific immunity
mechanical barriers
inflammation
chemical barriers
natural killer (NK) cells
phagocytosis
fever
42
what are the mechanical barriers against infection
mucous membranes and the skin
43
damaged tissues release chemicals that attract what to the site
white blood cells
43
what is inflammation
tissues response to damage, injury, or infection
44
what may occur in fluids that accumulate
clotting
45
what may form around the damaged tissue to aid in preventing the spread of pathogens
a CT sac
46
what are some examples of chemical barriers
enzymes in gastric juices
tears
low pH in stomach
high salt concentration in sweat
interferons
defensins
collectins
activation of complement proteins in plasma
47
what do interferons do
stimulate uninfected cells to synthesize antiviral proteins that block the growth of viruses, stimulate phagocytosis, and enhance activity of cells that help resist infections and stifle tumor growth
48
what do defensins do (more like offensins)
make holes in bacterial walls and cell membranes
49
what do collectins do
protect against a wide variety of microbes by binding to them and facilitating phagocytosis (they go around collecting microbes and host a killing party for them)
50
what is the activation of complement proteins in plasma
it stimulates inflammation, attracts phagocytes, and enhances phagocytosis (sets up the party, invites the friends (phagocytes), and hypes up the friends)
51
why are NK cells so slay?
they secrete perforins which kill cancer cells and cells infected with viruses (its giving vigilante) AND proinflammatory stuff
52
what are the most active phagocytes in the blood
neutrophils and monocytes
53
monocytes? more like mothercytes!
she gives rise to what cell...?
macrophages which can be free or fixed in various tissues
54
what are phagocytic cells associated with
the linings of blood vessels in the liver, spleen, and mononuclear phagocytic system
55
what causes a fever
when a viral or bacterial infection stimulates lymphocyte cells to secrete IL-1 which temporarily raises body temperature
56
how does a fever help fight infection
elevated body temperature results in elevated iron in the blood which increases phagocytic activity towards the infection
57
how does the body know the difference between self and non self antigens
during fetal development the body cells take an inventory of their own proteins and other large molecules, and then lymphocytes develop receptors that allow them to tell the difference between self and non self antigens
58
what are haptens
small molecules that can combine with larger ones, becoming antigenic
58
where to lymphocytes originate
in red bone marrow
59
what happens to lymphocytes once they are released into the blood
some make to to the thymus where they are turned into T cells, others mature in the red bone marrow to become B cells
60
where to both T and B cells reside
lymphatic tissues and organs
61
when are T cells activated
when an antigen presenting cell displays a foreign anatigen
61
each variety of T and B cell respond only to what
a specific antigen
62
what does a macrophage acting as an accessory cell do?
it phagocytizes an antigen bearing agent, digests the agent, and displays the resulting antigens on its cell membrane in association with certain MHC proteins
63
what to T cells react to
cell to cell contact (cellular immune response)
64
what to T cells secrete
cytokines such as interleukens, that enhance cellular response to antigens and stimulate proliferation of a T cell to enlarge its clone
T cells also secrete substances that are toxic to their target cell
65
when does a helper T cell become active
when its specific antigens are displayed
66
what does a helper T cell do once its activated
stimulates a type of B cell to produce antibodies for the specific antigen
67
what does a cytotoxic T cell do
recognize foreign antigens on tumor cells who's surfaces indicate that they're infected with a virus
68
what do cytotoxic T cells secrete
perforin to destroy cells infected with a virus
69
what do memory T cells do
allow for immediate response ti second and subsequent exposure to the same antigen
70
when are B cells activated
when it encounters an antigen that fits or when stimulated by a helper T cell
71
what do some B cells differentiate into
anti-body producing plasma cells
72
what is the humoral immune response
when antibodies react against the antigen bearing agent that stimulated their production
73
where do memory B cells come from
further differentiated B cells
74
what are immunoglobulins
soluble proteins called antibodies
74
what constitutes the gamma globulin fraction of plasma
immunoglobulins
75
what does each immunoglobulin consist of
four linked chains of amino acids
76
antigen-binding sites
variable regions at the end of the 4 amino acid chains of immunoglobulins that react with antigens
77
the 5 major types immunoglobulins
IgG, IgA, IgM, IgD, and IgE
78
which immunoglobulins make up most of the circulating antibodies
IgG, IgA, and IgM
79
what do antibodies do?
directly attack antigens
bind antigens to activate their complement
stimulate local tissue changes that are unfavorable to antigen bearing agents
80
what does the direct attack of an antigen result in (3 things)
agglutination
precipitation
neutralization
81
what do activated complement proteins do
alter infected cells to be more susceptible to phagocytosis
attract phagocytes
lyse foreign cell membranes
82
during the primary immune response, antibodies are produced for how long
several weeks
82
what is the primary immune response
B and T cells encountering an antigen that they are specialized to react to
83
what is the secondary immune response
memory cells rapidly respond to subsequent exposure to an antigen
84
what immunity protects populations
herd immunity
85
example of naturally acquired active immunity
a person encounters a pathogen and has a primary immune response
86
example of artificially acquired active immunity
a person receives a vaccine containing a dead or weakened pathogen
87
example of artificially acquired passive immunity
a person receives a vaccine with an antiserum or antitoxin
88
example of naturally acquired passive immunity
antibodies pass from mother to baby in utero
89
which lasts longer, active or passive immunity
active lasts much longer than passive
89
what is a hypersensitivity reaction
excessive misdirected immune response that may damage tissue
90
what is a type 1 hypersensitivity (immediate reaction)
a person is born with the ability to overproduce IgE in response to an allergen
91
what do allergic reactions actually result from
mast cells bursting and releasing allergy mediators like histamine
92
type 2 hypersensitivity (antibody-dependent cytotoxic hypersensitivity)
when a blood transfusion is mismatched
93
type 3 hypersensitivity (immune complex hypersensitivity)
involve autoimmunity and immune reactions against self antigens
94
type 4 hypersensitivity (delayed-reaction hypersensitivity)
can occur in anyone and inflame the skin, results from repeated exposure to chemicals or cosmetic products
95
what are MHC antigens
substance that helps the body accept foreign tissue from a transplant
96
autoantibodies (👎)
the little jerks responsible for autoimmune diseases :((( they attack the bodies own tissues
97
