Anatomy & Physiology 34B Lecture
Chapter 20 - Lymphatic System Anatomy
I.
Overview
A. Lymphatic System Overview
B. Lymph Nodes
C. Lymphatic Trunks
D. Lymphatic Ducts
II. _________________ System - consists of lymph, lymphatic vessels, lymphocytes, lymphatic
tissues & organs
A. ____________ of the lymphatic system include:
1. ________ ___________ - lymphatic vessels transport fluid that has escaped from the
blood vessels back to the blood stream
2.
________ ___________ - transports absorbed fats and some vitamins from the small
intestine to the blood
3.
_______________ -lymphocytes in lymphatic tissues help to provide immunological
defenses against disease-causing agents
B. Lymph & Lymphatic Vessels
1. The lymphatic system has been called the second circulatory system, but the fluid
within only travels toward the heart
2.
Lymphatic ____________ are closed-ended and form networks in the intercellular
spaces near blood capillaries of most tissues
a.
Lymphatic capillaries are highly permeable and collect _____ ________ that has
escaped from blood vessels
b.
This fluid in the lymphatic capillaries is called _____, which is similar to blood
______ in composition, but low in protein.
c.
__________ are lymphatic capillaries in the villi of the small intestine that
transport absorbed fats, in the form of _______, from the GI tract to the blood
stream
3.
Lymph moves from lymphatic __________  lymph collecting ______  lymph
______  lymphatic ________  lymphatic _______, which empty into the
____________ veins
4.
Lymphatic capillaries merge into larger lymph collecting __________ (LCVs), which
accompany blood vessels and have a structure similar to _______
a.
Superficial LCVs parallel superficial ______; deep LCVs of the trunk & digestive
organs accompany deep ________
b.
LCVs have the same three tunics as veins, and contain one way __________ to
prevent backflow
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c.
Lymph is moved via skeletal _______ and ________ pumps, and peristaltic
contractions of some lymph vessels
III. Lymph _______ - bean shaped organs located along the collecting vessels
A. Function to cleanse the lymph of _________
B. ___________ of lymph nodes include
1. ____________ nodes near jugular veins & carotid arteries
2. _____________ nodes in the armpit
3. ______________ nodes in the superior thigh (groin area)
4. Tracheo___________ nodes in the mediastinum
5. Aortic nodes along the abdominal _______
6. Iliac nodes along the _______ arteries
C. Lymph node structure and function
1. Lymph nodes are small bean shaped bodies enclosed in fibrous CT ____________
2. Lymph filters through the ____________ tissue of lymph nodes clustered along the
lymphatic vessels
3.
The outer cortex contains _______________ centers where B lymphocytes multiply
and differentiate into plasma cells when a pathogen enters the lymph node
4.
Several _________ lymphatic vessels carry lymph into the node, where it is circulated
through lymph ______ (irregular channels)
5.
While in the lymph node, macrophages and ____________ cells remove pathogens
from the lymph
6.
Lymph leaves the node via the ____________ lymphatic vessel, which emerges from
the hilum (a concave depression).
D. _______________ is a tropical disease caused by mosquito- borne round worms that
infect and block lymph nodes. This results in chronic edema and grotesquely swollen
extremities
E. ____________ are swollen lymph nodes, typically seen in people suffering with bubonic
plague, a disease caused by the bacterium Yersinia pestis
IV. Lymph Trunks
A. Lymphatic collecting vessels converge to form lymph _______
B. Five major lymph trunks, from inferior to superior are:
1. __________ - paired trunks along the sides of the aorta in the inferior abdomen;
drains the lower limbs, pelvic organs, & some of the abdominal wall
2.
__________ - single trunk near the posterior abdominal wall; receives _______
from digestive organs
3.
Bronchio____________ - paired trunks near trachea sides; collect lymph from the
thoracic viscera & thoracic wall
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4.
__________ - paired trunks near base of neck; receive lymph from upper limbs,
inferior neck, & superior thoracic wall
5.
___________ - paired trunks at base of each int. jugular vein; drain lymph from
head & neck
V. Lymphatic Ducts
A. Lymphatic trunks drain into lymphatic _______, the largest lymphatic vessels
B. The two major lymph ducts are the thoracic & right lymphatic
1. ____________ duct
a. Drains lymph from the lower extremities, abdomen, and ____ thoracic, upper
extremity, head & neck regions
b.
c.
2.
The trunk ascends the spinal column and drains into the left _____________ vein
The ______________ is a saclike enlargement of the inferior duct that collects
lymph from the lumbar and intestinal trunks
Right ______________ duct
a. Drains lymph from the ________ upper extremity, thoracic region, head & neck
b.
The duct empties into the right ____________ vein, near the internal jugular vein
VI. Lymphoid _________ & Lymphocytes
A. __________ - largest lymphoid organ, located to the left side of stomach, from which it
is suspended, in the abdominal cavity
1.
2.
In infants, it’s an important site for _____ production
In adults, it assists other organs in ____________ production, filtering blood, and
destroying old RBCs. It contains
a.
b.
_____ pulp destroys old ______ and pathogens
________ pulp with ___________ centers for lymphocyte production
B. Lymphatic ___________ within the lymph nodes are the sites of lymphocyte production.
1.
2.
3.
___________ - are an aggregation of large lymphatic nodules embedded in the mucus
membrane of the throat. three types are
a.
b.
_______ - largest, posterior to mouth & palate on throat sides
c.
Lingual - on posterior _______
Pharyngeal (________) - on roof of throat; infected palatine & pharangeal tonsils
are surgically removed (______ectomy)
Aggregated lymphoid nodules (_________ patches) are groups of lymphatic
nodules found in the ileum (3rd portion of the small intestine)
Over half the thickness of the ______________ wall is dense lymphoid tissue.
C. Lymphoid ___________ is CT where lymphocytes gather to fight invading
microorganisms. Two locations it is found include:
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1. Mucosa-associated lymphoid tissue (_______) – in mucous membranes of the
digestive, respiratory, urinary, and reproductive tracts.
2. All lymphoid organs except the ________.
D. __________ - located in the anterior thorax, deep to the sternal manubrium
1.
It is much larger in a _______ & child than in an adult and is an important site of
immunity
2.
It houses lymphocytes & changes undifferentiated lymphocytes into
___________________. Types of T lymphocytes include
a.
____________ T (CD4) cells - stimulate the production of B & T cells; works
with B cells to increase antibody production
b.
c.
d.
_____________ (killer) T (CD8) cells - cause lysis and death of foreign cells
_____________ T cells - inhibit proliferation of T cells after an immune response
____________ T cells - remain in lymphoid tissues for years and recognize
original invading antigens
E. Lymphocyte Activation
1. Lymphocytes originate in bone _______ as lymphoid ____ cells
a. Some migrate to the ________ to mature as T lymphocytes
b. Others remain in the ____ marrow to become B lymphocytes
2. __ & __ lymphocytes migrate to infected CT tissues, such as the lymph tissue in lymph
nodes, where they become fully activated.
3. __ lymphocytes stimulated by antigens on helper T cells become
a. __________ cells – create antibodies against the antigen
b. ____________ cells – create more plasma and memory cells rapidly if the same
antigen is encountered again.
4. ______________, B & T cells constantly patrol the bloodstream & lymphatic system.