Chapter 6 Flashcards
Lymph
The fluid that removes cellular waste products,
pathogens, and dead blood cells from
the tissues.is made up of the remaining 10% of
the returning interstitial fluid. Lymph is a clear, watery
fluid containing electrolytes and proteins. It plays essential
roles in the lymphatic system as it works in close
cooperation with the immune system.
n Lymph collects the protein molecules created within
the cells as it leaves. Lymph also removes dead cells,
debris, and pathogens (including cancer cells) that
were still left in the intercellular spaces.
n The lymph enters very small capillaries within the tissues
and then flows into progressively larger vessels
and ducts as it travels in a one-way trip upward toward
the neck.
n At this stage, the lymph begins to play an active role in
cooperation with the immune system to protect the
body against invading microorganisms and diseases.
These functions are described in the discussion of the
immune system.
Lymphatic vessels and ducts
The capillaries, vessels, and ducts that return
lymph from the tissues to the venous
bloodstream.
Lymph nodes
Bean-shaped structures of the lymphatic system
where pathogens and other harmful
substances are filtered from the lymph by
specialized cells of the immune system.
Tonsils and Adenoids
Lymphoid structures of the lymphatic system
that protect the entry to the respiratory system.
Spleen
A sac-like mass of lymphoid tissue with
protective roles in both the immune and
lymphatic systems
The spleen filters microorganisms and other foreign
material from the blood.
n The spleen forms lymphocytes and monocytes, which
are specialized leukocytes (white blood cells) with
roles to play in the immune system.
n The spleen has the hemolytic (hee-moh-LIT-ick)
function of destroying worn-out erythrocytes (red
blood cells) and releasing their hemoglobin for reuse
(hem/o means blood, and -lytic means to destroy).
n The spleen also stores extra erythrocytes (red blood
cells) and maintains the appropriate balance between
these cells and the plasma of the blood
Bone Marrow
Produces lymphocytes, which are specialized
leukocytes (white blood cells). Myel/o also
means spinal cord
Lymphocytes
Specialized leukocytes that play important
roles in the immune reactions.
Thymus
A gland located in the upper chest with
specialized roles in both the lymphatic and
immune systems.
anti-
against
carcin/o
cancerous
immune/o
immune, protection, safe
lymph/o
lymph, lymphatic tissue
lymphaden/o
lymph node or gland
lymphangi/o
lymph vessel
neo-
ne/o
new, strange
-oma
tumor, neoplasm
onc/o
tumor
phag/o
eat, swallow
-plasm
formative material of cells
sarc/o
flesh, connective tissue
spleen/o
spleen
-tic
pertaining to
tox/o
poison, poisonous
lymphatic system
- Absorb fats and fat-soluble vitamins through the lacteals
of the small intestine. - Remove waste products from the tissues, and cooperate
with the immune system in destroying invading
pathogens. - Return filtered lymph to the veins at the base of the
neck.
Lacteals
are specialized structures
of the lymphatic system that absorb those fats that
cannot be transported by the bloodstream. These
dietary fats are transformed in the cells of the lacteals.
The lymphatic vessels then return them to the venous
circulation so they can be used throughout the body as
nutrients
interstitial fluid
plasma blood that flows out of the arterioles and into the capillaries,
and then flows into the spaces between the cells of
the tissues.
n This fluid delivers nutrients, oxygen, and hormones to
the cells.
n When interstitial fluid leaves the cells, it brings with it
waste products and protein molecules that were created
within the cells. About 90% of this fluid returns to
the bloodstream.
Cool Lymph facts
Blood circulates throughout the entire body in a loop,
pumped by the heart. The bloodstream flows in an
open system in which it leaves and reenters the blood
vessels through the capillaries
n Since the lymphatic system does not have a pump-like
organ, it must depend on the pumping motion of
muscles to move the fluid upward.
n Lymph flows in only one direction. From its point of
origin, lymph can move only upward until it returns
to the circulatory system at the base of the neck.
Once lymph enters a lymphatic capillary, it must
continue this upward flow.
n Blood is filtered by the kidneys, and waste products
are excreted by the urinary system. Lymph is filtered
by lymph nodes, which are located along lymphatic
vessels. These nodes contain specialized cells of the
immune system.
n The color of blood makes the arteries and veins readily
visible. Since lymph is a clear fluid, the lymphatic
vessels are not readily visible.
Lymphatic Capillaries
are microscopic, blind-ended
tubes located near the surface of the body with capillary
walls that are only one cell in thickness. These cells separate
briefly to allow the lymph to enter the capillary. Then
the action of the cells as they close forces the lymph to
flow upward and forward
Lymphatic vessels
which are located
deeper within the tissues. Like veins, lymphatic vessels
have valves to prevent the backward flow of lymph.
The larger lymphatic vessels eventually join together
to form two ducts. Each duct drains a specific part of the
body and returns the lymph to the venous circulation
cervic
neck
axill
armpit