Lymphatic System Flashcards
(68 cards)
1
Q
- The Lymphatic System carries out the immune response through a network of lymphatic vessels that collect excess _______ from the body’s interstitial spaces, filters the fluid through lymph nodes then returns it to the bloodstream.
A
fluid (lymph)
2
Q
Interstitial fluid and lymph are basically the same. After the fluid leaves the _______ then enters lymphatic vessels, it is called ____.
o Lymph is usually transparent, watery & slightly yellow.
A
interstitial spaces
lymph
3
Q
- Specialized lymphatic capillaries are _____.
A
lacteals
4
Q
Lacteals occur in the __________ of the small intestinal lining. They absorb lipids from the intestinal tract.The lymph in lacteals is called _____ and is creamy-white in color due to presence of fat (lipids).
A
fingerlike projections (villi)
chyle
5
Q
What are the Functions of the Lymphatic System?
A
o 1) Drains excess interstitial fluid from tissue spaces.
o 2) Transports dietary lipids from the GI tract to the blood.
o 3) Protects against invasion through the immune responses.
6
Q
- Besides lymph, name some other things that the Lymphatic System consists of.
A
o Lymphatic capillaries
o Lymphatic vessels
o Agranular leukocytes called lymphocytes (the T-cells, B-cells, and natural killer cells)
o Thymus & spleen
o Lymph nodes
o Lymphoid nodules (Peyer’s patches, tonsils, and appendix)
7
Q
- Lymphatic vessels begin as close-ended vessels called _________ in spaces between tissue cells.
A
lymphatic capillaries
8
Q
- Lymphatic vessels occur throughout the body alongside arteries (in the ______) or alongside veins (in the _________).
A
viscera
subcutaneous tissue
9
Q
- Lymphatic vessels are absent from what?
A
- central nervous system
- bone marrow
- teeth
- avascular tissues (cornea, epidermis, hyaline cartilage).
10
Q
- Similarities to Veins include:
o Lymphatic vessel valves are present to prevent the backward flow of _____.
o Walls of lymphatic vessels consist of the same three _____, but the _____ are thinner and poorly defined in lymphatic vessels.
o Lymphatic vessels receive nutrients from _______ (vessels of vessels).
A
lymph
tunics, tunics
vasa vasorum
11
Q
- Differences to Veins include:
o Lymphatic vessels are ______
o Lymphatic vessels have a larger ______.
o Lymphatic vessels have thinner ______
o Lymphatic vessels have anchoring filaments; are _______- type fibers extending from the endothelial cells of lymphatic capillaries to surrounding tissue space.
o Ends of the _________ making up the wall of lymphatic capillaries overlap to keep the lymph in.
A
- Differences to Veins include:
o Lymphatic vessels are ______
o Lymphatic vessels have a larger diameter.
o Lymphatic vessels have thinner tunics
o Lymphatic vessels have anchoring filaments; are collagenous- type fibers extending from the endothelial cells of lymphatic capillaries to surrounding tissue space.
o Ends of the endothelial cells making up the wall of lymphatic capillaries overlap to keep the lymph in.
12
Q
The Flow Pattern of Lymph:
A
- interstitial spaces (interstitial fluid)
- lymphatic capillaries (lymph)
- lymphatic vessels (lymph)
- lymphatic trunks (lymph)
- lymphatic ducts (lymph) à subclavian veins (blood plasma)
- arteries (blood plasma)
- blood capillaries (blood plasma)
13
Q
- Lymph passes from lymphatic capillaries into lymphatic vessels which merge to form _________.
A
lymphatic trunks
14
Q
There are nine major lymphatic trunks.
o They include:
A
lumbar, jugular, subclavian, and bronchomediastinal each of which occurs in pairs (left & right for each side of the body) and a SINGLE intestinal trunk.
15
Q
- The nine major trunks pass their lymph into two main channels: ________ aka __________ & __________. From these channels lymph turns into ____________.
A
thoracic duct aka left lymphatic duct & right lymphatic duct.
venous blood
16
Q
- The thoracic duct is 15-18” in length.
o It begins as enlarged region of the lymphatic vessel.
o _____ + _______ + _______ = enlarged region called cisterna chyli.
A
o Intestinal trunk + right lumbar trunk + left lumbar trunk = enlarged region called cisterna chyli.
17
Q
- Right lymphatic duct is ½” in length.
o Thoracic Duct & Right Lymphatic Duct drains into the _________ at their junctures with the internal jugular veins.
A
left and right subclavian veins
18
Q
The lymphatic duct empties right where _______ breaks off into the ____ and _____ veins.
A
brachiocephalic
subclavian and internal jugular veins
19
Q
- Drainage of right lymphatic duct:
A
o Receives lymph from:
- Upper right side of the body
- Right upper limb
- Right region of the chest
- Right region of the head
- Right region of the neck
20
Q
- Drainage of thoracic duct:
A
o Receives lymph from:
- Left side of the head
- Left side of the neck
- Left side of the chest
- Left upper limb
- The entire body inferior to the ribs
21
Q
The ______ carries lymph originating in tissues inferior to the diaphragm and from the left side of the upper body. The smaller right ______ carries lymph from the rest of the body.
A
thoracic duct
lymphatic duct
22
Q
- The flow of lymph from tissue spaces is maintained by:
A
o 1) primarily the contraction of skeletal muscles
o 2) one-way valves (similar to those in veins)
o 3) Respiratory pump
23
Q
- The primary lymphatic/lymphoid structures of the body are _______ (in flat bones such as the sternum, ribs, and cranial bones and the epiphyses of long bones such as the humerus and femur) and the ______.
A
red bone marrow
thymus gland
24
Q
- Red bone marrow and the thymus gland are termed ________ because they produce T-cells, B-cells, and natural killer cells which are the lymphocytes that carry out immune responses.
A
primary lymphatic structures
25
The __________ of the body are the lymph nodes, spleen, plus the lymphatic nodules.
major secondary lymphatic structures
26
***Most immune responses occur in secondary _________!***
lymphatic structures
27
________ Leukocytes – Lymphocytes (T-cells, B-cells, and the natural killer cells)
Agranular
28
______: attack fungi, transplanted cells, and cancer cells
T-cells
29
_______: destroy bacteria (the little structures coming off the _____ are antigen receptors)
B-cells
30
_________: attack certain spontaneously arising tumor cells
Natural killer cells
31
The _____ is a 2-lobed gland lying between the sternum and base of the heart in the superior, and a bit of the anterior, mediastinum
thymus
32
* *At 10-12 years old the thymus reaches the maximum size of _____, then slowly atrophies (by age 65, it weighs ~6 grams and is simply a fatty tissue) ** - Its function is also at its max at this age.
* Note: This is why when you are younger it is easier to fight off infection, bacteria, and disease due to the thymus.
40 grams
33
The thymus does NOT provide a filtering function, like lymph nodes, since there are NO _________ leading into the thymus
afferent lymphatic vessels
34
What is the function of the thymus?
* Function is to promote the maturation of T-lymphocytes/T-cells
35
Each thymus lobule consists of an ____ and a _____.
outer cortex and a central medulla
36
Immature ________ migrate via the blood from red bone marrow to the thymus cortex where they multiply and develop into mature _____.
T-cells/pre-T-cells
* Note: T-cells are not functioning yet, they mature at the thymus gland.
37
T-cells migrate into the ______ where they leave the thymus by medullary blood vessels .
thymus medulla
38
* The thymus secretes the hormone ______.
| It assists in promoting the proliferation and maturation of T-cells.
thymosin
(Thymosin is produced in the medullary region in order to allow T-cells to mature in the thymus gland.)
39
* The _____ does NOT provide a filtering function, like lymph nodes, since there are NO afferent lymphatic vessels leading into the _____.
spleen
40
The _____ blood vessels and ______ vessels pass through the hilum of the spleen.
splenic blood vessels and lymphatic vessels
41
The spleen is surrounded by a capsule of _________.
The capsule gives off inward extensions called _______ (or septa).
dense fibrous connective tissue
trabeculae
42
Two areas of the spleen:
1) _____ is mostly B-cells arranged around central arteries
2) _____ consists of venous sinuses filled with blood & splenic/Billroth’s cords that lie between the sinuses.
1. white pulp
| 2. red pulp
43
* Function of the two areas of the spleen:
1) _____ is the site of B-cell proliferation into plasma cells
2) ____ carries out the main function of the spleen which is phagocytosis of bacteria & worn-out or damaged RBCs and platelets.
1. White pulp
| 2. Red pulp
44
Red pulp also functions as a _______ for blood platelets.
reservoir
45
The ______are filled with all sorts of immune structure – T-cells, B-cells, and macrophages.
splenic cells
46
What is the main function of the spleen?
phagocytosis
47
* Lymph nodes are small, 0.04-1”, bean-shaped structures located along the length of ________ and embedded in _______. (Normal lymph nodes are up to 1” in size, however lymph nodes fighting off infection are a lot larger.)
length of lymphatic vessels and embedded in connective tissue
48
Lymph nodes are scattered throughout the body and heavily concentrated in the _____, _____, and _____gland areas.
inguinal, axillary, and mammary gland areas.
49
Lymph nodes are surrounded by a capsule of ______ connective tissue. The capsule gives off inward extensions, like the thymus and spleen, called _______.
dense fibrous
trabeculae
50
The trabeculae divide the lymph node into compartments, provide framework support, and convey blood vessels into the interior of a node
They are specialized into two regions: _____ and _____.
cortex and medulla
51
The _____ is the outer region of densely packed T-cells and immature B-cells.
cortex
52
The _____ is the inner region of mature B-cells.
medulla
53
The ______ contain masses of actively proliferating lymphocytes.
germinal centers
54
The ______ are thin inward extension, from the cortex toward the hilum, of T-cells, B-cells, and macrophages.
medullary cords
55
Basically, how lymph flows through a lymph node:
_______ carry lymph from tissues to the lymph node; the vessels enter the convex side of the node. They contain valves that open toward the node so lymph is directed inward.
_______ carry lymph from the hilum (concave side of the node) to venous circulation. Contain valves that open away from the node to convey lymph out of the node.
Afferent lymphatic vessels
Efferent lymphatic vessels
56
A bit more detailed explanation of how lymph flows through a lymph node:
o Enters lymph node via afferent lymphatic vessels
o Lymph flows through lymph node in a network of sinuses (sinuses are passageways through the cortex and medulla between the medullary cords through which lymph moves toward the hilum)
o From ________sinus – between capsule and cortex
o Through cortex via cortical sinuses
o Through medulla via medullary cords
o Into hilum
o Exit lymph node via efferent lymphatic vessels
subscapular
57
There are a lot more afferent vessels coming to lymph nodes compared to the ones leaving (efferent). Why?
This will take longer to get fluid out; it gives it a lot longer time for lymph to get cleansed.
58
What are the functions of lymph nodes?
o ONLY lymphatic tissue that filters lymph, does so by the lymph entering one end of the node and exiting the other end of the node
* Foreign substances are filtered from the lymph BEFORE the lymph passes back toward the bloodstream
* Macrophages destroy some foreign substances by phagocytosis while other lymphocytes destroy foreign substances via immune responses.
* Monocytes can transform into macrophages; their main function is phagocytosis.
* Plasma cells and T-cells that have proliferated within a lymph node also leave and circulate to other parts of the body
59
ONLY _______ that filters lymph, does so by the lymph entering one end of the node and exiting the other end of the node.
lymphatic tissue
60
Foreign substances are filtered from the lymph before or after the lymph passes back toward the bloodstream?
BEFORE
61
____________ destroy some foreign substances by phagocytosis while other lymphocytes destroy foreign substances via immune responses.
Macrophages
62
_______ can transform into macrophages; their main function is phagocytosis.
Monocytes
63
_______ cells and __-cells that have proliferated within a lymph node also leave and circulate to other parts of the body
Plasma cells and T-cells
64
* Lymphatic nodules are NOT surrounded by a _____. They are clusters of lymphocytes that stand guard in all mucous membranes.
* They protect against bacteria and other pathogens that may enter the GI, respiratory, reproductive, and urinary tracts.
o They are referred to as ______.
capsule
mucosa-associated lymphoid tissue (MALT).
65
* An example of Lymphatic nodules: ________
This occurs in mucosa lining the ileum of the small intestine. This contains macrophages that capture and destroy bacteria thereby preventing microbes from breaching the intestinal wall.
Peyer’s Patches
66
* Another example of lymphatic nodules: _______
They create a ring of lymph tissue around the entrance of the pharynx. They function to gather and remove many pathogens entering the pharynx.
Tonsils
67
o Types of tonsils:
* One __________- embedded in the posterior wall of the nasopharynx; mass of lymphatic nodules
* Two ________ tonsils- lie at the posterior region of the oral cavity
* Two ________ tonsils- located at the base of the tongue
pharyngeal tonsil/ adenoid
palatine
lingual
68
* Another example of lymphatic nodules: _________
It contains large groupings of lymphatic nodules. It is located in the lamina propria of mucosa, and, a bit, in submucosa.
Appendix
