Lecture #6 Flashcards
Functions of the Lymphatic System
- Fluid Recovery
- Immunity
- Lipid
Immunity 3 lines of defence?
- External Barriers
- Skin, mucous membrane, trachea - Non-specific (innate) Defense Mechanism
- protective proteins, cells, and processes - Adaptive Immune System
- Leaves body with a memory of the pathogen
Pathogen
Viruses, bacteria, fungi, parasites , toxins
Innate Immunity Principal characteristics
- is rapid response
- fixed
- broad specificities
- constant
Adaptive Immunity principal characteristics
- slow response
- variable
- numerous highly selective specificities
- improve during response
Innate Immunity consists of ….
Two parts
- Pathogen recognition
- Recruitment of destructive effector mechanism
Antimicrobial Proteins
-creates a pore in the membrane and destructs the infected cell
- interferons
- complement pathways
The Innate Immune response causes Inflammation
- Bacteria is introduces
- Vasodilation occurs
- Infected tissue becomes inflamed, causing redness, heat, swelling and pain
Adaptive Immunity consists of …..
1) Specificity
2) Memory
Classes of Adaptive Immunity
- Natural Active Immunity - production of owns antibodies/ T cells as a result of natural exposure to an antigen
- Artificial Immunity - production of owns antibodies or T cell by vaccination
- Natural Passive Immunity - Temporary immunity that results from acquiring antibodies produced by another person ie. baby and mom
- Artificial Passive Immunity - temporary immunity that results from injection of an immune serum obtained by another person i.e. snake bites
B cell encounters a antigen
mature into a plasma cell which secretes antibodies
T cells encounter antigen
mature into Effector T cells;
- cytotoxic T cells - kill cells with virus
- Helper T cells - secrete cytokines, help with immunity and controls activities of other T cells
Antigen
Structure on macromolecule, virus, or cell that is recognized and bound by an immunoglobin (ig’s) and T cell receptors
Humoral Immunity
- immunity due to antibodies
- neutralization
- opsonization - flagging for destruction coating of pathogen by antibody to facilitate phagocytosis
Vaccination
Serve disease prevented by prior exposure to the infectious agent in a form that cannot cause disease
Cardiovascular system
heart and blood vessels
circulatory system
heart, blood vessels, and the blood
Left side of the heart
pumping blood to all the organs in the body
Right Side of the heart
pumps blood into pulmonary truck
Function of valves
- ensure one way blood flow
- open and close in response to changes in pressure
Atrioventicular Valves
- one way flow from the atria to ventricles
- tricuspid means 3 cups/ leaflets
-bicuspid means one way flow from the ventricles to pulmonary artery or aorta
pulmonary semilunar valve
aortic semilunar valve
Valves of the Heart have
chordae tendinae: attach to papillary muscles
- prevents backward explosion (prolapse)
Diastole
- ventricles are relaxed
- pressure drops inside ventricles
- semilunar valves close as blood tries to back up
- AV valves open
- Blood flow from atria to ventricles
Systole
- Ventricles contract
- AV valves close as blood tries to back up
- pressure rises inside of ventricles
_ semilunar valves open and blood flow into great vessels
Heart has its own circulatory system
5% of blood bumped by the heart is to pump the heart through the coronary circulation
Angina
Angina pectoris – is chest pain from partial obstruction of coronary blood flow
Myocardial infarction (MI)
Heart Attack –sudden death of a patch of myocardium resulting from long-term obstruction of the coronary circulation
Myocardial Ischemia
ischemia means lack of blood flow
Automaticity
describes that heart cells can spontaneous depolarize to threshold without any information
Rhythmicity
heart’s conduction is in a regular manner, ie. regular generation of an action potential
Electrical conduction through the heart
- electrical signal initiates muscle contrations
- electrical signals travel from cell to cell through gap junctions
- Conduction system — coordinates the heartbeat
Pacemaker of the heart is located
in the right atrium
Membrane Potentials
Intracellular K+> (greater than) Extracellular K+
Intraceullar Na< (less than) Extracellular Na+
Pacemaker
Sa node does not have a stable resting membrane potential
- starts at -60mV
- gradual depolarization called pacemaker potential
- reaches threshold og -40mV K+ channels open and repolarization occurs
- K+ channels close, pacemaker potential starts again
SA nodes fire every 0.8 seconds setting the Resting Rate at 75bpm
q
Cardiac Action potential
- Na+ channels open
- Na+ depolarizes the membrane and opens more Na+ channels
- Na+ channels close, voltage peaks at nearly +30mV
- Ca2+ enters slowing, prolongs depolarization,creates plateau. falls slightly b/c K+ leakage
- Ca+ channels close and Ca2+ is transported out of the cell. K+ channels open and rapid K+ outflow returns membrane to its resting potential
Electrocardiograms (ECG/EKG)
measure the electrical activity of the heart
P wave
SA node fires, atria depolarize and contracts
PQ segment
Atrial contraction (atrial systole)
QRS complex
- ventricular depolarization
- complex shape of spike due to different thickness and shape of the two ventricles
ST segment
ventricular systole
T wave
ventricular are depolarizing and relaxing
Pressure
impels fluid to move
- according to pressure gradient (high to low)
Resistance
opposes flow