Lymphatic System (EXAM #2) Flashcards
1
Q
Overview of the Lymphatic System?
A
- Lymphatic system consists of:
- One way network of lymphatic vessels that collect ~10% of the extracellular fluid that leaked out from cardiovascular capillaries and return this fluid (now termed lymph) to the venous blood
- Lymph nodes along the vessel network that cleanse lymph as it passes through them
- Contain T & B lymphocytes that identify and remove bacteria, viruses, cancer cells
- Lymphoid cells, tissues and organs support the functions of the lymphatic system
2
Q
What are the 2 types of Body Fluid Compartments?
A
- Intracellular Fluid
- Extracellular Fluid
3
Q
Intracellular Fluid
A
Fluid found within cells (~40% of body weight)
4
Q
Extracellular Fluid
A
- Fluid found outside of cells
- Blood Plasma
- ISF (interstitial fluid)
- Lymph
5
Q
Blood Plasma
A
- ~5% of body weight)
- Fluid in blood
- Some exits capillaries to form ISF
6
Q
ISF (interstitial fluid)
A
- ~15% of body weight
- Fluid between cells within the body (except blood cells which are surrounded by plasma)
- Some moves into lymphatic capillaries to form lymph
7
Q
Lymph
A
- ~1% of body weight
- Fluid inside lymphatic vessels
- Returned to blood plasma
8
Q
Lymphatic Circulation (PART 1)
A
- Lymph enters lymphatic capillaries (closed ended vessels that project into cardiovascular capillary beds)
- Lymphatic capillaries in the small intestine also play a role in fat absorption
- Lymphatic capillaries connect to larger lymphatic collecting vessels that have one-way valves
9
Q
Lymphatic Circulation (PART 2)
A
- Lymph nodes along collecting vessels filter lymph (bacteria, debris)
- Transports lymph fluid AWAY from tissues to:
1. Right Lymphatic Duct
2. Thoracic Duct
- Transports lymph fluid AWAY from tissues to:
- Fluid flows through lymphatic collecting vessels largely as a result of body movements (muscle
contractions) that move the fluid toward the heart. One-way valves in the collecting vessels prevent back
flow of lymph.
10
Q
Right Lymphatic Duct
A
- Lymph from the right side of the head, chest,and arm
- Drains into right subclavian vein re-entering circulation
11
Q
Thoracic Duct
A
- Lymphs from below the ribs and the entire left side of the body
- Collecting vessels from below the ribs coverage to an enlarged lymph vessel = cisterna chyli (this is the most inferior portion of the thoracic duct)
- The thoracic duct drains into the left subclavian vein reentering blood circulation
12
Q
One Way Route back to Blood (Circulation)
A
- Lymphatic capillaries
↓ - Lymphatic collecting vessels (with valves)
↓ - Lymphatic ducts
↓ - Subclavian veins
13
Q
Lymphoid Tissues & Organs
A
- Contain many lymphocytes and play a key role in the body’s immune system
- Include:
- Primary lymphoid organs and tissues
- Secondary lymphoid organs and tissues
14
Q
Primary lymphoid organs and tissues
A
- Locations where lymphoid stem cells divide and mature (become immunocompetent)
- Include:
- Red Bone Marrow
- Thymus Gland
- Mature lymphocytes move into blood stream and migrate to the secondary lymphoid organs/tissues
15
Q
Red Bone Marrow
A
- All lymphocyte stem cells arise here
- Site of B lymphocyte proliferation (mitosis) maturation
16
Q
Thymus Gland
A
- Early in development (fetal stage) lymphocyte stem cells migrate here
- Site of T lymphocyte proliferation (mitosis) and maturation
17
Q
Secondary Lymphoid Organs and Tissues
A
- Where lymphocytes detect and remove pathogens
- Locations where lymphocytes are activated and proliferate further
- Includes:
- Lymph nodes
- Spleen
- Mucosal Associated Lymphoid Tissue (MALT)
18
Q
Lymph nodes
A
- Small masses of lymphoid tissue along lymphatic collecting vessels
- High concentrations of lymph nodes are located in:
- Cervical (neck), axillary (armpit), inguinal (groin), intestinal, pelvic regions
19
Q
Spleen
A
- Located in left side of abdominal cavity just below diaphragm next to stomach
- Filters (cleans) blood by removing pathogens (organisms that can cause disease like bacteria or viruses), old and defective blood cells, and cellular derbis
20
Q
Mucosal Associated Lymphoid Tissue (MALT)
A
- Trap and remove pathogens at points of entry into the body
- Includes tonsils, appendix, and other lymphoid tissues on mucous membranes
- e.g. aggregated lymphoid nodules (Peyer’s patches) in the small intestine
- e.g. tonsils: form a ring around the pharynx
- Pharyngeal (1)
- Palatine (2)
- Lingual (1)
21
Q
Pharyngeal (1)
A
In posterior nasopharynx (referred to adenoids when infected/swollen)
22
Q
Palatine (2)
A
In oropharynx - used to be commonly removed
23
Q
Lingual (1)
A
Bumpy nodules on posterior part (base) of tongue
