Know filtration and reabsorption through arteries, lymph tissue, and veins.
how many liters flow into lymph tissue?
Arteries → filtration through arterial end → tissue → reabsorption through venule end
* 3.6 Liters flow into the lymph tissue
what are these and where do they empty into the cardiovascular system?
Thoracic Duct - empties into left subclavian vein and jugular vein
Cisterna Chyli
what are the 5 tonsils in the wall of the pharynx?
know tonsillitis.
Pharyngeal tonsil (adenoid - prone to cancer)
Left and right palatine tonsils - can see this one
Two lingual tonsils - below palatine tonsils
*tonsillitis - inflammation of tonsils
Innate defenses (both slides):
1. Physical barriers - skin, epithelial layers of internal passageways
- Secretions that flush away, kill, or inhibit materials
- Sweat, mucus, urine, enzymes, antibodies, stomach acid
2. Phagocytes - macrophage, neutrophil, eosinophil, monocyte
- Macrophages can be fixed or free
3. Immune surveillance - natural killer cells
- Golgi apparatus produces vesicles containing Perforins, which dissolve the plasma membrane of abnormal cell, “Perforate” the other membrane
4. Interferons - chemical messengers which are released by lymphocytes, macrophages, or virus-infected cells
- coordinate the defense against viral infections
- Cytokines are a type of messenger released by tissue cells
- Complement - group of 30 special circulating proteins that assist antibodies in fighting. Like a group of police. Also lyses cells, enhances phagocytosis and
inflammation. Liver response. - Inflammation - tissue level response
- Redness (rubor), Swelling (tumor), Heat (calor), Pain (dolor), Loss of function (functio laesa)
- Effects of inflammation:
- necrosis (local tissue destruction)
- Pus - mix of debris, fluid, dead and dying cells, and necrotic tissue
- Abscess - accumulation of pus in an enclosed space
- Fever - increase in body temperature that speed up tissue metabolism
- Pyrogens - fever producing agents
- Produced by bacteria, molds, viruses, and yeasts, Cause hypothalamus to raise body temperature
- Pyrogens - fever producing agents
antibody structure - just go over image.
Antibodies Structures - just know light and heavy chain, variable segment (changes), constant segment
- Light chain
- Variable segment & constant segment
- Heavy chain
- Variable segment & constant segment
Summary of the Lymphatic System - read through…
what are pathogens?
what is the definition of immunity?
Lymphatic system is a group of organs, vessels, and tissues that protect from infection, disease, pathogens…
Pathogens are organisms such as viruses, bacteria, fungi, parasites…
Immunity is the ability to resist infection and disease.
overall, what are the components of the lymphatic system?
what are the primary and secondary organs & tissues?
- Lymph - fluid similar to plasma, but without plasma proteins
- Lymphatic vessels and lymphatic nodes - carry lymph from peripheral tissues to veins
- Lymphoid tissues and lymphoid organs - tonsils, appendix, thymus, spleen, mucosa-associated lymphatic tissue (malt), red bone marrow.
- Primary - red bone marrow, thymus
- Secondary - tonsils, spleen, lymph nodes, patches in large intestine, MALT
(Mucosa is lining of internal organ - digestive, respiratory, urinary, and reproductive tracts)
- Lymphoid cells - lymphocytes, phagocytes, and other cells
what are the functions of the lymphatic system?
Produce, maintain, and distribute lymphocytes and other lymphoid cells
Return excess fluid to bloodstream
Maintain normal blood volume
Transport hormones, nutrients, and wastes
Lymphatic Vessels:
what is their job?
what are these vessels made of? what is their structure?
what are lacteals?
(know that you have superficial and deep lymphatics)
- Job is to carry lymph
Lymphatic capillaries: - Closed at one end (important) rather than forming a tube
- Have larger luminal diameters and thinner walls
- Have flat or irregular outline in sectional view
- Endothelial squamous cells are loosely bound together for movement of fluid through tissue. Overlap of endothelial cells acts as a one-way valve, like shingles on a roof to promote movement.
- Lacteals (know for exam) -
Special lymphatic capillaries in small intestine that transport lipids from digestive tract
what is lymphedema?
- Blockage of lymph drainage from a limb
- Causes severe swelling
- Interferes with immune system function
Lymphoid cells & lymphocytes:
name 3 different lymphocytes and where they come from.
what is lymphocyte production called? where does production occur?
Make 20-40% of circulating leukocytes (wbc)
Most are stored, not circulating
Wander through tissues
Enter blood vessels or lymphatics for transport
Can survive many years
Hemocytoblasts in bone marrow > two types of lymphoid stem cells:
Group 1: B Cells (Bone marrow derived) & - Natural Killer Cells (NK Cells - also come from bone marrow.)
Group 2: T Cells (Thymus-dependent) - travel to thymus and differentiate with exposure to hormones
*Lymphocytopoiesis - occurs in bone marrow, thymus, and peripheral lymphoid tissue
Lymphoid Tissue is connective tissue dominated by lymphocytes.
:)
what are lymphoid nodules?
how are they different from lymph nodes?
Areolar tissue with densely packed lymphocytes:
- Lymph nodes, spleen, respiratory tract (tonsils), along digestive, urinary, and reproductive tracts
- Smaller than lymph nodes, not as defined of a structure
*Germinal center contains dividing lymphocytes
what does MALT stand for?
where is it?
- mucosa-associated lymphoid tissue
- Lymphoid tissues associated with digestive system
remember the appendix!
know appendicitis
- Contains a mass of fused lymphoid nodules
- Appendicitis is inflammation of the appendix
Lymph Nodes:
1. what is the difference between afferent and efferent lymphatics?
2. what are the functions of lymph nodes?
3. where are the largest lymph nodes?
4. what is lymphadenopathy?
- Afferent lymphatics (many coming in)
Carry lymph from peripheral tissue to lymph node - Efferent lymphatics (only 1 going out)
Leave lymph node and carry lymph to venous circulation
- Afferent lymphatics (many coming in)
- functions: Purify lymph, quality checker, remove 99% of antigens
- Antigens released due to infection
- Antigens can stimulate macrophages and lymphocytes in each lymph node
- Largest lymph nodes: Groin, axillae, and base of neck
- Swell in response to infection
- Lymphadenopathy: May indicate Cancer of lymph system
- Chronic or excessive enlargement of lymph nodes
*know that Lymph nodes of gut, trachea, lungs, thoracic duct protect against pathogens in digestive and respiratory systems.
- Chronic or excessive enlargement of lymph nodes
Thymus:
what takes over the work for the thymus after puberty?
where is the thymus?
what is Thymosin?
Atrophies after puberty → bone marrow takes over the thymus work
- Located in mediastinum
- Mature T cells leave thymus by medullary blood vessels
- Thymosin - Extract containing several hormones that promotes development and maturation of T cells
Spleen:
what are the functions of the spleen?
know splenectomy.
(doing about 80% of the work)
- Removal of abnormal blood cells and other blood components by phagocytosis
- Storage of iron recycled from rbc
- Initiation of immune response by B cells and T cells
- Phagocytes and other lymphocytes in spleen identify and attack cells in circulating blood
what is the definition of immunity?
what is resistance?
what is an immune response?
what is immunocompetence?
name the 2 types of immune responses. (will go into detail on each in another card)
- Immunity - Ability to resist and defend against infection organisms and other damaging substances
- Resistance - ability of body to maintain immunity
- Immune response - body’s reaction to infectious agents and other abnormal substances
- Immunocompetence - ability to produce immune response after exposure to antigen
- Innate (nonspecific) immunity - born with immunity. Natural mechanism. Always works the same way against any type of invading agent
- Adaptive (specific) immunity - develops after exposure to environmental hazards
what is Adaptive (specific) Immunity?
what is an example of Artificially Active Immunity?
what is an example of Artificially Passive Immunity?
- Adaptive Immunity develops after exposure to environmental hazards
Many different types, only need to know memory T Cells- Memory T Cells - respond to antigens previously encountered
Active Immunity and Passive Immunity
1. artificially active immunity - eg. Through vaccines
2. Artificially passive immunity - eg. donating serum with antibodies during covid
- Injection of antibodies
what are Immunoglobulins?
where are these from?
Immunoglobulins (lgs) - classes of antibodies from mothers breast milk
just know the responses to antigen exposure…
First exposure - primary response
Next exposure - secondary response
(Like exposure to covid)
Immune Disorders: there are 3 categories, read through…
- Allergies (or hypersensitivities) - eg. food allergies, pollen, toxins, chemicals, viruses, bacteria…
Categories:
- Type 1 - Immediate hypersensitivity- Rapid, severe
- most common, includes environmental allergies
- May cause Anaphylaxis - can be fatal, affects whole body, smooth muscle contraction in respiratory, peripheral vasodilation - Antihistamines can block histamine to relieve mild symptoms
- Type 2 - Cytotoxic reactions
- Type 3 - Immune complex disorders
- Type 4 - Delayed hypersensitivity
- Autoimmune disorders - body reacts to and attacks itself
- Cells make auto-antibodies against own body cells
- Eg. thyroiditis, rheumatoid arthritis, Type 1 diabetes - Immunodeficiency diseases - Problems with embryological development of lymphoid organs and tissues
- Can result in HIV or AIDS
- Immune system diminishes with age
- Nervous and endocrine systems influence immune response
