Physiology exam 4

• The lymphatic system is the network of vessels that recovers fluid pushed out by the blood.

  The lymph collects in nodes where the immune cells will inspect the fluid.

  Lipid absorption is when the dietary lipids get absorbed out

  primary lymph organs are: red bone marrow and thymus

  Secondary lymph organs are: lymph nodes, tonsils, and spleen
• The red color of blood depends on how rich the hemoglobin is of oxygen (44%)
• Anemia: really low RBC

  Polycythemia: really high RBC

  Leukopenia: really low WBC

  Leukocytosis: really high WBC

  leukemia: cancer of bone marrow. causes high # of immature WBC
• plasma is made up of:

  92% water

  7% plasma proteins

  1% ions

  plasma is the extracellular fluid similar to intersitial fluid
• Plasma Proteins:

  Albumin (58%)- smallest and most abundant. exerts colloid osmotic pressure. acts as transport for proteins

  Globulins (37%)- acts as transport for proteins. includes gamma globins, immuno globins, antibodies.

  Fibrinogen (4%)- contribute to blood clot formation

  regulatory proteins (1%)- Enzyme and hormones
• Mycloid line forms erythrocytes, all leukocytes except megakaryocytes

  lymphoid line form only lymphocytes
• Erythrocytes are small and flexible, lack a nucleus and cellular organelles. they transport oxygen and CO2 between tissues and lungs.

  consists of 4 subunits: Iron at the center for 4 oxygens to bind

  lifespan of 120 days
• Erythropoietin controls the production of RBC.

  it is a hormone produced in the kidney and is stimulated by low O2 in RBC.
• Blood doping increases RBC to enhance athletic performance.

  comes with the risk of inc. viscosity and inc. in heart attacks and strokes.
• Blood type A has A antigens and antiB antibodies (it is compatible with A and O)

  Blood type B has B antigens and antiA antibodies (it is compatible with B and O)

  Blood type AB has AB antigens and no antibodies (it is compatible with everyone(

  Blood type O has both A and B antibodies meaning it can only recirve O Blood but donate to all

  rH system is the + or - of blood which shows presence of D antigen.

  rH - can be given to both + and -
• there are 5 types of leukocytes:

  Granulacytes have visible granules and contains 20-70% Neutrophils which phagocytizes infectious pathogens. Eosinophils make up 1-4% and are active with parasitic worm infection. Basophils make less than 1% and promotes inflammation.

  Agranulocytes are not visible and has 20-40% lymphocytes and 2-8% monocytes

  Pneumonic: Never Let My Engine Blow 60,30,6,3,0
• Platelets are small membrane-enclosed fragments that break off from megakaryocytes in red marrow with no nucleus and are important in clotting
• pulmonary circulation moves blood from lungs and the heart while systematic circulation moves blood from the heart to the cells
• The anatomy of cardiac muscle has sarcolemma and sarcoplasma same as skeletal muscles. in intercellular structure, cells are connected by intercalated discs. these cells are joined mechanically (desmosomes) and electrically (gap junctions)
• the conduction system initiates and conducts electrical events to ensure proper timing of contractions. nodal cells have action potential but do not contract. the influence of the parasympathetic system can decrease heart rate while the sympathetic system can increase heart rate and force of contraction.
• Nodal cells in the SA node initiate a heartbeat which starts with sodium channels opening up when the threshold of -60 (hyperpolarization) occurs. after reaching the threshold of -40, calcium channels open and depolarize the cell. after peaking, potassium channels open where potassium will leave the cell and repolarize the cell until it reaches -60 where Na begins to enter once more.
• cardiac muscle cells has a RMP of -90mV. first, impulses open sodium channels which will depolarize the membrane from -90 to +30mV where sodium channels will begin to deactivate.

  Next potassium leaves the cell and calcium enters the cell which causes a flat plateau.

  calcium channels close while potassium stays open to repolarize the membrane and bring rmp back to -90
• p wave- reflects atrial electrical charges from the SA node due to depolarization

  QRS complex- ventricular electrical changes due to depolarization

  T wave- ventricular electrical changes from repolarization

  PR interval- atrial action potential

  PQ segment- atrial contraction

  QRS complex- ventricular depolarization

  QT segment- ventricular action potential

  ST segment- ventricular plateau

  
• ventricular fibrillation is electrical signals traveling randomly due to heart not pumping blood efficiently (no coronary perfusion). hallmark of a heart attack and is characterized by having no QRS complex, no t wave, no plateau (weak signal)
• Atrial fibrilation is when the atria beats fast and irregularly and is identified by no Pwave before QRS complex
• Heart block is where the heart fails to conduct any signals. usually result of degeneration of conductive system. identifies by a smaller QRS than P wave (sometimes not even present)
• The cardiac cycle is the repeated patterns of phases which are systolic (contraction) and diastolic (relaxation).
• End-diastolic volume is the total volume of blood in the ventricles at the end of diastole

  End-systolic volume is the total volume of blood left in the left ventricle after systole (1/3 of the end diastole volume)

  stroke volume is the amount of blood that gets ejected amount
• cardiac output is the amount of blood pumped out the left ventricle per minute and is calculated by heart rate x stroke volume(mL) = cardiac output (L)
• vessel types:

  • Arteries--arterioles- have a thick tunica media and a narrower lumen than veins
  • Veins--venules- have a thick tunica externa and a larger larger lumen (will collapse if no blood is in the vessels)
  • Capillaries contain only tunica intima which is thin to allow for gas exchange
• Aneurysn is when part of the arterial wall thins and ballons out causing it more prone to rupture (more common in aorta)
• 3 types of capillaries:

  1. Continuous capillaries have tight junctions connecting cells but it doesn't form a complete seal. least permeable, larger proteins cannot enter and is finding skeletal, muscle, skin, and CNS
  2. Fenestrated capillaries have fenestration (pores) which is found in areas with a lot of fluid transport like the intestine, and absorbing nutrients.
  3. Sinusoids are most permeable and are identified as a thin lining with big holes and gaps around it, allowing passage of larger things. can be found in the bone marrow and spleen
• Varicose veins also known as spider veins is a condition when venous valves can no longer close effectively and cause veins to enlarge their surface.

  this can be of a result of genetics, standing for a long time, and obesity. it can be treated by walking, and compression socks
• Deep vein thrombosis is when a blood clot forms in one or more deep veins in the body from lack of movement for some time.

  preventatives are walking and compression stalkings
• Hydrostatic pressure is the pressure exerted by fluid which pushes blood out of the vessel and promotes filtration. interstitial fluid hydrostatic pressure is the pressure exerted by fluid into the vessel which is usually around 0mmHg.

  Colloid osmotic pressure is the pull of water into the vessel due to the preassure of protein solutes. Blood colloid osmotic pressure is the opposite force of hydrostatic pressure. interstitial fluid colloid osmotic pressure draws fluid into the interstitial space which the pull is relatively low (0-5)
• Net filtration pressure is the difference between the Net Hydrostatic pressure and the Net colloid osmotic pressure. it can be calculated by (HPb-HPif)-(COPb-COPif).. (if number is negative, that means the pull is greater which will reabsorb at the venous end)
• An edema is an excessive accumulation of intersitial fluids. which can be caused by :

  1. high arterial blood pressure
  2. leakage of plasma proteins into interstitial fluid
  3. Decrease plasma protein concentration
  4. Obstruction of lymphatic drainage
• Blood volume is the body water distribution in the body, the more blood volume, the higher the blood pressure.

  The antidiuretic hormone stimulates water reabsorption and thirst due to excessive salt intake, dehydration, or high plasma osmolarity which as a result increases blood volume.

  Angiotensin 2 is stimulated by thirst and causes vasoconstriction/peripheral resistance and produces aldosterone in the adrenal cortex.
• when blood pressure is low, the renin-angiotensin-aldosterone system stimulates the release of the enzyme renin in the kidneys. Renin converts angiotensinogen from the liver into angiotensin 1 which after going through the lungs, angiotensin-converting enzyme transforms angiotensin 1 to angiotensin 2. Angiotenis 2 stimulates vasoconstriction and release of aldosterone in the adrenal cortex which will stimulate salt retention and water retention.

  Inhibitor angiotensin-converting enzyme (ACE inhibitor) prevents conversion of angiotensin 2. used to treat hypertension
• Atrial nutriuretic peptide are the antagonist of RAAS. they have receptors in the atria which stimulate the release of atrial natriuretic peptide which excretes salt and water from the kidneys. it also inhibits ADH secretion

  Epinephrine and Norepinephrine are released by sympathetic system to bind to alpha receptors and cause vasoconstriction
• The baroreceptor reflex is activated by changes in blood pressure detected by baroreceptors and results in increased heart rate and peripheral resistance. good for quick beat-by-beat such as lying down to standing
• pulse pressure measures the HR, pulse pressure is the difference between systolic and diastolic which is used to reflect store volume
• An Angiogram is an x ray picture of the coronary arteries with iodine dye used to detect narrowing arteries for assessing coronary artery disease
• Coronary artery bypass grafting (CABG) is grafting of a vessel taken from a patient into the aorta so that it bypasses the narrowed coronary artery
• Coronary angioplasty is a technique used by inserting a balloon into an occluded site of a coronary artery to keep open