Immune System - Lymphatic And Immune Flashcards
What is immunity?
- Ability to resist damage from pathogens, toxins and internal threats
What makes up the immune system?
- Lymphoid tissues / Lymphatic System
- Immune cells
- Chemicals that coordinate and carry out immune functions
- “self ” from “non-self” - a targeted response
What are the functions of the immune system?
- Recognize and remove abnormal “self ” cells
- Removes dead or damaged cells
- Protects the body from disease-causing invaders
What are the types of responses of the immune system?
- Nonspecific Innate Immunity and Specific Acquired Immunity
What is the lymphatic system?
- System of vessels / cells / organs that carries excess fluids to the bloodstream and
filters pathogens from the blood - drain body fluids and return them to the bloodstream
What is the lymph?
Lymph: interstitial fluid (fluid that fills spaces between cells) once it has entered
the lymphatic system
What is the function of the lymphatic system?
- Fluid Balance
- Lipid Absorption
- Defence against pathogens
What makes up the lymphatic system?
Tonsils, the lymph nodes, the spleen, the thymus
What are lymph nodes + where are they located?
Lymph nodes -located along lymphatic vessels
* Groups in the cervical (neck), axillary (armpit), and inguinal
(groin) areas
Describe the way lymph is able to carry fluid from tissues to the circulatory system
- Vessels begin as open-ended capillaries,
- Feed into larger lymphatic vessels
- Empty into the bloodstream by ducts.
- Lymph travels through the lymph nodes
- Doesn’t circulate ie not pumped by heart
- Forced through the vessels by contraction of skeletal muscles
What are the function of the capillaries in the lymphatic system? + characteristics
- Where fluid enters the lymphatic
system - In virtually all tissues
- between arterioles and venules
- Thinner walls than veins
*fluid moves into the capillaries only (in one direction)
What does the lymphatic system entail in the small intestine?
*found in vili of GI tract
*lymphatic capillaries called lacteals
*lipids and some lipid soluble vitamins form a milky fluid = chyle
*this fluid enters the lacteals and blood stream
Outline lymphatic circulation
- Lymphatic capillaries → Vessels → Trunks →2 ducts
Describe drainage in the right duct and left duct
- Right: Right lymphatic duct drains into right subclavian vein
- right sides of the head, thorax,
and right arm - Left: Thoracic duct drains
into the left subclavian vein - remaining portions of the body
What is lymphatic tissue?
*lymphocytes/ defence cells
Where are lymphocytes found?
red bone marrow
What type of tonsils are lymphatic?
- Palatine tonsils
- Pharyngeal tonsils (adenoids when enlarged)
- Lingual tonsil
Where are lymph nodes located + how they involve in lymph travel?
- Distributed along the lymphatic vessels
- Lymph passes through before entering
blood - Superficial or deep
*lymph flows through the nodes
Describe how lymph nodes get rid of pathogens
- Superficial aggregations
- (1) inguinal nodes in the groin, (2) the axillary
nodes in the axilla (armpit), and (3) the cervical
nodes in the neck. - Dense capsule with extensions: trabeculae
- lymphatic tissue: Lymphocytes and lymphatic
nodules - lymphatic sinuses: macrophages
macrophages remove pathogens
What does the spleen do?
*filters blood
= responds to foreign substances, destroy old RBC
What is found In the spleens?
*white pulp
*red pulp
What is white pulp + what is its role?
- Lymphatic tissue surrounding arteries
- Lymphocytes can be stimulated to divide
What is red pulp + what is its role?
- Surrounding veins
- Macrophages and red blood cells
- Macrophages remove foreign substances
and worn-out red blood cells through
phagocytosis
*also a blood reserviour
What is the thymus and what is it composed of?
- 2 lobed gland
- Divided into lobules
- Cortex (dark)
- Many lymphocytes
- Medulla (light)
- Fewer lymphocytes
- Maturing T-cells
- Mature T-cells migrate to medulla, enter blood and travel to other lymphatic tissue
