LYMPHATIC SYSTEM Flashcards
originate as small, dead-end tubes
called lymphatic capillaries
Lymphatic vessels
The unidirectional valves divide lymphatic vessels
into a series of chambers, which function as “primitive
hearts.
” Lymph moves into a chamber, smooth muscle in
the chamber wall contracts, and lymph moves into the
next chambe
1.Contraction oflymphatic vessels
Form a one-way system
Lymphatic vessels
Excess fluid passes through the tissue spaces and
enters lymphatic capillaries to become lymph.
flows only toward the heart
Lymph
lymphatic vessels
are compressed, causing lymph to mov
2.Contraction of skeleta
During inspiration, pressure in the thoracic cavity decreases,
lymphatic vessels expand, and lymph flows into them. During
expiration, pressure in the thoracic cavity increases, and
lymphatic vessels are compressed, causing lymph to
Thoracic pressure changes
Are round, oval, or bean-shaped structures ranging from 1mm to 25mm long. It is distributed along the various lymphatic vessels.
Lymph nodes
After passing through the lymph nodes, the lymphatic vessels converge to form larger vessels called ___, each of which drains lymph from a major portion of the body
lymphatic trunks
filter lymph before it is returned to the blood
Lymph nodes
engulf and destroy bacteria, viruses, and
other foreign substances in lymph
- Macrophages -
respond to foreign substances
- Lymphocytes -
Contains phagocytic macrophages
Medulla inner part
Contains follicles- collections of
lymphocytes
Germinal centers enlarge when antibodies are released by plasma cells
- Cortex (outerpart)
Jugular trunks drain lymph from the head and neck
Subclavian trunks drain lymph from the upper limbs, superficial
thoracic wall, and mammary glands
Bronchomediastinal trunks drain lymph from the thoracic
organs and the deep thoracic wall
Intestinal trunks drain lymph from abdominal organs, such as the intestines, stomach, pancreas, spleen, and liver
Lymphatic ducts -large veins in the thorax or join to yet larger
vessels which then connect to the large veins
Right lymphatic duct -joins a right thoracic vein, it drain lymph from
the right side of the head, upper-right limb, and right thorax
Thoracic duct -drains lymph from the right side of the body inferior
to the thorax and the entire left side of the body
Cisterna chyli -is a dilated sac at the lower end of the thoracic duct
which lymph from the intestinal trunk and two lumbar lymphatic
trunks flow
When the body is exposed to microorganisms or other foreign substances, the lymphocytes _____ that destroys microorganisms and foreign
substances
divide, increase in number, and become
part of the immune response
Small masses of lymphoid tissue deep to the mucosa surrounding
the pharynx (throat)
Tonsils
Trap and remove bacteria and other foreign pathogens
Tonsils
Tonsillitis results when the tonsils become congested with bacteria
Three groups of tonsil:
1.Palatine tonsils
2.Pharyngeal tonsil
3.Lingual tonsi
Destroys worn-out blood cells
SPLEEN
Located on the left side of the abdomen
SPLEEN
Filters and cleans blood of bacteria, viruses, debris
SPLEEN