3 (20) The Lymphatic System Flashcards Preview

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Flashcards in 3 (20) The Lymphatic System Deck (24)
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1
Q

What are the three functions of the lymphatic system?

A

draining interstitial fluid, transporting dietary lipids, protection

2
Q

Describe the structure of a lymphatic capillary. How does it work?

A
  • made of a single layer of squamous epithelial cells
  • slightly larger than blood vessels
  • cells overlap and act as one-way valves
  • opened by pressure of interstitial fluid
  • anchoring filaments attach cells to surrounding tissue
3
Q

Where would we find lymphatic capillaries and where are they absent in the body?

A
  • found in tissue spaces between cells

- absent from the central nervous system, bone marrow, teeth, avascular tissues, splenic pulp

4
Q

What is lymph? Is it a circulating fluid?

A
  • interstitial fluid and leaked plasma proteins drain into lymphatic capillaries
  • NOT a circulating fluid
5
Q

Trace the flow of lymph from the lymphatic capillaries to the collecting ducts.

A

lymphatic capillary, lymphatic vessel, lymph node, lymphatic vessel, lymphatic trunk, collecting duct

6
Q

What are the two major lymphatic ducts, and what areas of the body do they drain?

A

THORACIC DUCT - 3/4 of the body

RIGHT LYMPHATIC DUCT - drains right arm, and right side of head, neck and upper torso

7
Q

Where do the two major lymphatic ducts empty into the circulatory system?

A

both empty into subclavian veins at junction with internal jugular vein

8
Q

Where would you find the cisterna chyli?

A

lower end of the thoracic duct (in most mammals) into which lymph from the intestinal trunk and two lumbar lymphatic trunks flow

9
Q

What are the organs of the lymphatic system?

A

PRIMARY ORGANS - red bone marrow, thymus gland

SECONDARY ORGANS - lymph nodes, lymph nodules, spleen

10
Q

Describe the structure and function of a lymph node.

A

STRUCTURE #
- vary in shape and size but most bean shaped
- external fibrous CAPSULE
- TRABECULAE extend inward and divide node into compartments
- two histologically distinct regions: Cortex, Medulla
# FUNCTION #
- provide biological filtration
- immune system activation—lymphocytes activated and mount attack against antigens
- site of cancer growth and metastasis

11
Q

What is the medical name for a swollen lymph node?

A

buboes (singular: bubo)

12
Q

What does albumin do for the blood?

A

regulates osmotic pressure

13
Q

What happens when the flow of lymph is blocked?

A

lymphedema, which means swelling due to a blockage of the lymph passages

14
Q

What are lacteals and what do they do?

A
  • specialized lymphatic capillaries in vili of small intestine
  • transport lipids
15
Q

What are lymph nodules?

A

small, localized collection of lymphoid tissue, usually located in the loose connective tissue beneath wet epithelial (covering or lining) membranes, as in the digestive system, respiratory system, and urinary bladder

16
Q

What is MALT?

A

mucosa associated lymphoid tissue

17
Q

What are Peyer’s patches?

A
  • small masses of lymphatic tissue found throughout the ileum region of the small intestine
  • form an important part of the immune system by monitoring intestinal bacteria populations and preventing the growth of pathogenic bacteria in the intestines
18
Q

What are tonsils?

A

lymphoid tissue under the mucous membranes of the throat

19
Q

Name the three major tonsils.

A
  • (1) the pharyngeal tonsils, commonly known as adenoids
  • (2) the palatine tonsils and (3) the lingual tonsils, which are lymphatic tissue on the surface tissue of the base of the tongue
20
Q

What does the thymus do?

A
  • does not directly fight antigens

- functions strictly in T lymphocyte maturation (keeps isolated via blood thymus barrier)

21
Q

Where is the thymus?

A

inferior neck; extends into mediastinum; partially overlies heart

22
Q

When is the thymus largest? Then what happens to it?

A

grows in size and most active during childhood, then stops growing during adolescence and then gradually atrophes

23
Q

Locate the spleen. What is white pulp? Red pulp?

A
  • upper left quadrant of abdomen
  • WHITE PULP: little islands, mostly B cells
  • RED PULP: connective tissue (the cords of Billroth) and many splenic sinusoids that are engorged with blood (red color) primary function - is to filter the blood of antigens, microorganisms, and defective or worn-out red blood cells
24
Q

What are the three functions of the spleen?

A
  • site of lymphocyte proliferation and immune surveillance and response
  • cleanses blood of aged cells and platelets, macrophages remove debris
  • stores breakdown products of RBCs for later use and stores blood platelets and monocytes