Exam 3 Flashcards
Primary & Secondary Lymphnoid organs
Primary: Thymus and bone marrow (because they produce T & B cells)
Secondary: spleen, appendix, tonsils, lymphnodes
T & B cells
T-cells: born in bone marrow, educated (immunocompetence) in the **Thalmus. ** Then gather mainly in the spleen and lymphnodes. Only mature when they actually fight.
B-cells: Born and educated in the bone marrow. Travel to fight infection.
Lymphnode
Germinal center is where T & B cells are dividing.
cancer spreads and is trapped in lymphnodes
Spleen
Largest of all lymph organs. During fetal development its the site on hematopoises.
Cleansing function: removal and destruction of pathogens and old blood cells.
Pulps:
** white-** concentration of WBC (immunity)
**red:** concentration of RBC
Tonsils
Simplest lymphoid organs
Four groups of tonsils:
Palatine, lingual, pharyngeal, and tubal (opening of auditory tube) tonsils
Arranged in a ring (crypt) to gather and remove pathogens
Underlying lamina propria consists of MALT
Function of Lymphatic system
- Return excess tissue fluid back to blood pool (if not, we would have 2-4L in our interstitial spaces)
- Return leaked proteins (maintains osmotic pressure)
- Return fat (chyle)
- Fight disease (pathogens are agents/microorganisms that can cause disease)
Lymph & Tissue fluid
- Lymph - blood filtered through capillary walls; contains plasma, water, ions, sugars, proteins, gases, amino acids - is colorless, but low in protein compared to blood plasma
- Tissue fluid - Watery fluid that, along with the molecules of ground substance, occupies the extracellular matrix of connective tissue; it is a filtrate of the blood containing all the small molecules of blood plasma; also called interstitial fluid.
order of lymph vessels
- Lymphatic capillaries are the smallest and first to receive lymph.
- Lymphatic collecting vessels collect from lymph capillaries.
- Lymph nodes are located along these collecting vessels.
- Lymph Trunks
- Lymph Ducts empty in the veins of the neck.
Lymphatic trunks
- Lumbar trunks – receives lymph from lower limbs and lumbar region
- Intestinal trunk – receives chyle from digestive organs
- Bronchomediastinal trunks – collects lymph from thoracic viscera
- Subclavian trunks – receive lymph from upper limbs
- Jugular trunks – drain lymph from the head and neck
Lymphatic Ducts
• Thoracic duct – ascends along vertebral bodies
o Empties into venous circulation
o Junction of left internal jugular and left subclavian veins
o Drains three quarters of the body
o Body parts they drain – the left side of the head, neck, and thorax; the left upper limb; and the body’s entire lower half
• Right lymphatic duct
o Empties into right internal jugular and subclavian veins
o Body parts they drain – right jugular, subclavian, and bronchomediastinal trunks
Cisterna chyli – located at the base of the Thoraciic duct at the union of lumbar and intestinal trunks
Regional nodes
Axillary, cervical, and inguinal
** What is an antigen/pathogen?**
- Antigen - A molecule that is recognized as foreign by the immune system, activates the immune system, and reacts with immune cells or antibodies.
- Pathogen - a bacterium, virus, or other microorganism that can cause disease.
Edema
Abnormal accumulation of tissue fluid in the loose connective tissue; causes the affected body region to swell.
-Standing for long times at work my develop it
** Elephantiasis**
a condition in which a limb or other part of the body becomes grossly enlarged due to obstruction of the lymphatic vessels, typically by the nematode parasites that cause filariasis.
o Lymph nodes become swollen usually from bacterial or viral infections.
T cells
bind to antigens that are present by special proteins that occur only on the membranes of eukaryotic cells. Only responds to foreign antigens. Anything with altered (antigenic) proteins on their surface.
B cells
differentiate into plasma cells that secrete antibodies. Antibodies are proteins that bind to specific antigens and mark them for destruction by, making them more recognizable to phagocytic cells
** Monocytes**
transforms into macrophages, phagocytic cells that move by amoeboid motion through connective tissue and ingest a wide variety of foreign cells, molecules, and tiny particles of debris
How do lymphatic vessels differ from those of the CV system in structure/ how are they similar?
- Both of these systems work in a similar manner. They both produce liquid substances — blood and lymph — that move through their networks of vessels and ducts to various parts of the body. Each of these liquid substances carries nutrients or removes waste. As such, both could be considered circulatory in nature.
- The circulatory system is primarily responsible for transporting blood throughout the body. It’s made up of the heart, the organ that pumps blood, and the veins and arteries that move blood to and away from body tissues. Blood transport is crucial because this substance carries many nutrients and fluids that the body needs for sustenance, such as oxygen.
- The lymphatic system acts as a waste removal system for the body. When unneeded material is absorbed by the muscles, lymph picks up this material and transports it to the lymph nodes, where it is ingested. Old and unusable red blood cells are eliminated in this way, meaning that the circulatory system uses the lymphatic system as a means of disposal.
- The blood plays a major role in creating lymph. Blood plasma becomes a substance known as interstitial fluid when it comes into contact with body tissues. Some of this fluid enters lymphatic vessels, where it is then transformed into lymph. In fact, one of the primary responsibilities of the lymphatic system is to drain interstitial fluid from tissues.
MALT
mucosa associated lymphoid tissue
Lymphatic Collecting Vessels
Accompany blood vessels (arteries and veins)
Composed of the same three tunics as blood vessels (tunica intima, media and externa)
Contain more valves (one way)
Helps direct the flow of lymph
Lymph propelled by:
Bulging of skeletal muscles
Pulsing of nearby arteries (lymph vessels share a common connective tissue sheath)
Tunica media of the lymph vessels
Lymph Capillaries
Located near blood capillaries, but closed at one end
High permeability allows:
Uptake of tissue fluid from connective tissue due to high pressure
Entrance of bacteria, viruses, and cancer cells
characteristics of lymph nodes
• Medulla
o The medullary cords are cords of lymphatic tissue, and include plasma cells, macrophages, and B cells
o The medullary sinuses are vessel-like spaces separating the medullary cords. Lymph flows into the medullary sinuses from cortical sinuses, and into efferent lymphatic vessels.
• Hilus – lymph exits from this indented region
• Afferent vessels – enters the node through this and has a valve
• Efferent vessels – exits after hilum
• Capsule – dense connective tissue that surrounds the node
• Trabeculae – invaginations of capsule
What is lymphoid tissue, what does it do and where do you find it?
• The main/important tissue of the immune system; a reticular connective tissue that houses and activates many lymphocytes.
• Macrophages on the fiber network kill invading microorganisms by phagocytosis and, along with dendritic cells, activate nearby lymphocytes by presenting them with antigens.
Found in
• Infected mucous membranes of the digestive, respiratory, urinary, and reproductive tracts.
• All lymphoid organs except the thymus
Lymphnodes
Function
Lymph percolates through lymph sinuses
Have afferent and efferent vessels with node acting as a “bottleneck” to slow the flow to allow time for cleaning.
Antigens destroyed – and activate B and T lymphocytes
approximately 500
organized in clusters
Bean-shaped
Situated along collecting vessels
NOT glands
Heart Location
- *Base**- inferior border of second rib
- *Apex**- rests on diaphragm and in between 5th and 6th rib
- *Tilts** to the left and anteriorly
heart chambers, valves, septa and blood vessels leading to and away from the heart.
Heart chambers (4)
• Right and left atria
• Right and left ventricles
Valves (4)
• Right atrioventricular (tricuspid) valve
• Left atrioventricular (bicuspid) valve
• Aortic (semilunar) valve
• Pulmonary (semilunar) valve
Septa
• Interventricular septum
• Interatrial septum – tissue between L and R atria
Blood vessels
• Arteries take blood away from the heart
• Veins take blood toward heart
pericardial membranes and layers of the heart wall.
3 Pericardial membranes
• Fibrous pericardium (provides anchoring, structural support and electrical insulation)
• Parietal layer of serous pericardium
• Epicardium (visceral layer of serous pericardium)
Heart Wall
• Epicardium
• Myocardium
• Endocardium
chordae tendinae & papillary muscles
• Papillary muscles (anchor chordae tendinae, which prevent AV valves from opening during ventricular contraction)
nodes and bundles for conduction and the path of the impulse through the heart
- Sinoatrial (SA) node: pacemaker
- Internodal bundles
- Atrioventricular (AV) node
- Atrioventricular bundles (bundle of His)
- Bundle branches
- Purkinje fibers
angioplasty & bypass
- Angioplasty - involves inserting a catheter into the patient’s arm or leg and threading it through the arteries until it enters the blocked coronary artery. When the catheter reaches the blockage, a balloon located on the tip of the catheter is inflated to exert pressure on the plaque-filled wall of the vessel. This pressure compresses the plaque and increases the diameter of the vessel lumen, thus improving blood flow to the myocardium.
- Bypass - vessels from another part of the body are used to reroute blood to the heart. A portion of a vessel is removed from its original location and grafted between the aorta and the heart wall, thus supplying an alternate route for blood to the heart muscle
Systole vs Diastole
- Systole - ventricles or the atria of the heart contract.
- Diastole - ventricles or atria of the heart relax.
Innervation , Parasympathetic (Vagus), & Sympathetic
- Innervation alters rate of contraction (chronotropy) and force of contraction (inotropy) – it does not cause the contraction
- Parasympathetic (Vagus) - slow down (20bpm or even stop; Ach binds to mACh receptors) - SA would normally beat at 100bpm, but vagal tone slows it down. Mostly affect chronotropy (innervate SA and AV nodes)
- Sympathetic – speed up (230bpm; epinephrine binds to β1 receptors). Affect chronotrophy and inotrophy (innervate SA node, AV node, and ventricles)
systemic / pulmonary/ cardiac circulations
• Pulmonary circulations - carries blood to and from the lungs for the uptake of oxygen and the removal of carbon dioxide
• Systemic circulations - carries oxygenated blood throughout the body and picks up carbon dioxide from body tissues
• Cardiac circulations - brings blood from the heart to the muscular layer of the heart wall. This gives the muscles the oxygen necessary to be able to pump blood. It also carries away carbon dioxide waste.
functions of the heart
- (1) Its right side receives oxygen-poor blood from the body tissues and then pumps this blood to the lungs to pick up oxygen and dispel carbon dioxide
- (2) its left side receives the oxygenated blood returning from the lungs and pumps this blood throughout the body to supply oxygen and nutrients to the body tissues
coronary sulcus and the coronary vessels
- R and L coronary arteries are the only branches of the ascending aorta; both travel in coronary sulcus to supply blood to heart wall. Their openings are immediately superior to the aortic semilunar valve (behind the cusps)
- R coronary artery branches into R marginal artery “small cardiac vein” (supply right border of heart) and posterior interventricular artery (supply both ventricles)
- L coronary artery branches into anterior interventricular artery (supply anterior surface of both ventricles and most of interventricular septum) and circumflex artery (supplies left atria and ventricle)
anterior and posterior interventricular sulcus and the vessels you find there.
- Anterior interventricular sulcus-Anterior interventricular artery/Great cardiac vein
- Posterior interventricular sulcus-Posterior interventricular artery/middle cardiac vein
right and left atria
structures
Right atrium
• Auricles – flaps projecting anteriorly
• Posterior part has smooth wall, anterior part lined with pectinate muscles
• Crista terminalis – ridge between anterior and posterior parts
• Fossa ovalis – depression in the interatrial septum that marks spot from opening in fetal heart (foramen ovale)
• Openings to coronary sinus, inferior vena cava and superior vena cava.
• Right AV valve (= tricuspid)
Left atrium
• Mostly smooth with pectinate muscle in auricle
• Openings to left pulmonary veins
• Left AV valve (= bicuspid = mitral)