U2: C9: Cardiovascular System

Question 1

Blood vessel flow from (deoxygentated from body) to (oxygentated to body)

Answer 1

body -> vena cava -> right atrium -tricuspid-> r ventricle -semilunar valve-> pulmonary artery -> lungs (drop off CO2 and pick up O2) -> p vein -> left atrium -bicuspid-> l ventricle -semilunar valve -> aorta -> body LAb RAt (bicuspid=mitral, tricuspid) Ventricular valves: semilunar valves

Question 2

Arteries vs Veins (direction relative to heart, width, elasticity, characteristic, pressure)

Answer 2

Veins: Visit the heart (fetal heart): thin, inelastic, valved, with adjacent muscles, lowest pressure at vena cava Arteries: Away from the heart (fetal heart): thick, smooth muscles w/in, elastic, highest pressure at aorta (left heart is more muscular bc it has to pump against higher pressure). Pressure drops the most from arterioles to capillaries (capillaries single epithelial cell can’t withstand much pressure).

Question 3

Heart contraction stimuli?

Answer 3

1. doesn’t require a stimulus, cardiac muscle is myogenic, they contract and electrical conduction establish contractions. 2, heart can be innervated by the vagus nerve to increase or decrease contraction rate.

Question 4

Heart electrical contraction steps

Answer 4

1. SA node (RA) -> (RA & LA) -> AV node (R AV) -> Bundle of HIS (septum) -> Purkinje FIbers (apex to ventricles)

Question 5

EKG

Answer 5

shows the electrical signals not the muscle contractions

Question 6

Systole vs Diastole

Answer 6

Systole: Ventricles contract -Atrioventricle valves close (LAB RAT) -Blood flows out of semilunar valves to body -BP rise Diastole: Ventricles relax (gauge pressure) -Semilunar valves closed -Blood fills ventricles -BP drops

Question 7

Osmotic pressure vs Hydrostatic Pressure

Answer 7

Osmotic Pressure: fluid into vessels (same for both venules and arterioles) Hydrostatic Pressure: fluid out of vessels (net pressure of Osmotic and Hydrostatic will determine the direction of flow fluid. At arterioles- flow out, venules- flow in)

Question 8

Blood content

Answer 8

Plasma (55%), Cell (45%) Plasma: water, salts (Na+, K+, Ca2+, Mg+, Cl-, Bicarbonate Cell: erythrocyte, leukocytes, platlets

Question 9

Blood types (RBCs)

Answer 9

AA, AO, BB, BO, AB, OO AB- universal recipient OO- universal donor Rh+ = protein on the surface of RBC’s

Question 10

Blood transports (gases)

Answer 10

Oxygen- Hemoglobin allostericly binds to O2 (sigmoidal curve), O2 affinity 1/p O2 dissociation. -pH decrease, pCO2 and temperature increase = O2 dissociation increase and O2 affinity decrease Carbon dioxide- via carboic annhydride converted into bicarbonate which is dissolved in plasma and transported. It is a blood buffer.

Question 11

Blood transports (nutrients )

Answer 11

Carbs & Amino Acids: absorbed in SI, enter systemic circulation via the hepatic portal circulation (liver).

Fats: absorbed in SI as lacteals, bypass liver and enters directly into systemic circulation via thoracic duct, in blood packaged into lipoproteins (LDL), liver may take up LDL -> HDL (HDL= healthy)

Question 12

Clotting Mec

Answer 12

Collagen exposure Platletts aggregate & release clotting factors & clump Clotting factor: -Thromboplastin converts prothrombin-> thrombin -Thrombin converts fibrogen-> fibrin Fibrin: protein nest that catches RBC and forms clot and scab.\

1. Platlet plug formation: ound + platelts -> plateletsclump at wound, release cheicals,activates clotting factors
2. Coagulation: serioes of clotting factor/ enzyme activation that ends in firbinogen -> fibrin. Fibrin bein the fiber mesh that seals the cloth.
3. Retraction ad repair: clot contracts, get compact, but after the wounded lod vessels repairs itself, the clot dissolves.

Question 13

Blood origin to maturation

Answer 13

Sttem Cell (BM)

Multipotent Progenital Cell

Lymphoid Myeloid

Lymphoid

1. Precursor of Matrix
   
   1. B cell (spleen & lymph)
      
      1. Plasma
2. Precurosrs of Defense
   
   1. T cell (thymus)
      
      1. T cell
      2. NK cell

Myeloid

1. Precursors of LEUKOCYTES
   
   1. Agranular cells
      
      1. Macrophage (monocytes in PNS)
      2. Microgilla (macrophage ofr CNS)
   2. Granular cells
      
      1. Neutrophill
      2. Basophill
      3. Eosinophill
2. Precursors of Blood cells except for wbc
   
   1. Megacaryocyte
      
      1. Platlets
   2. Erytrhoblasts
      
      1. RBC (grave yard- spleen and liver, contain no organelles in order to cary as much gas for transport)

Question 14

Lympathic system Major functions (7)

Answer 14

1. equalization of fuid distribution
   
   1. interstital fluid pressure > lymphatic pressure -> lymph vessel flaps open -> interstital fluid enters lymphatic capillaries –> lymphatic circulation merges with veins –> returns the fluid to blood
   2. interstital fluid pressure < lymphatic pressure -> lymph vessel flaps close -> prevents lymph from leaking back out
2. Transport of proteins and large glycerides
   
   1. fats get absorbed into lacteals in SI
   2. lacteal = lymphatic capilalry in SI
   3. plasma protein that leaked into interstitl flud get returned to blood via the lymphatic system
3. Maturation of lymphocytes involved in immune reactions
   
   1. lymphocytes reside, proliferate, and differentiate (lymph nodes and thymus)

Question 15

Lymphoid tissue

Answer 15

Lymph nodes (concentrated with wbcs)

Thymus (where T cell mature)

Question 16

Lymphocytes Function

Answer 16

in lymphatic tissue, cleans & filters lymph.

When pathogens or foreign antigens get indisde a lymph node, lymphocytes get activated.

Question 17

Lymphocyte activation

Answer 17

lymphocytes start releasing chemicals that stimulate an immune response = proliferation, antibody production, release of cytokines.