Chapter 18- The Blood
Blood compostion- 55% Plasma, 45% (Erythrocytes, Leukocytes and cell fragments)
Physical Characteristics- alkaline PH 7.35, 5-6 liters in men, e-5 in woman
Functions of Blood- Transportation, Regulation, Protection
Erythroppietin- Hormone that stimulates RBC production/ Anemia- too low RBC Polycythemia- Too high RBC
Hemopoiesis- Process by which formed elements develop
Red Blood Cell (erythrocytes)- Contain hemoglobin, leave marrow and are destroyed at 2 mil per second
RBC Physiology- Specialized for Oxygen transport, atp anaerobically, globin-protien, heme-pigment
Erythropoieses- Production of RBC’s
BLOOD GROUPS- Antigen A on RBC= Type A
Antigen B on RBC= Type B
Both Antigens on RBC= Type AB
Niether Antigens on RBC= Type O
Whatever antigen is in the blood there will be the opposite Anti body in the plasma.
White Blood Cells(leukocytes)- have nucleus, no hemoglobin
Granular- Eosinophils-combats effects of histamine
Basophils-Release heparin,hystomine, and serotonin- Intensifying allergic response Neutrophils- Release lysozyme, antibiotic activity against fungi
Agranular- Monocytes- cleanup cellular debris, develop into macrophages
Lymphocytes- B-cells differentiate into cells that produce antibodies
T-cells- Attack viruses, cancers, bacteria, etc
Hemostasis- Sequence of responses that stops bleeding.
Hemostasis sequence- Vascular spasm, platelet plug forming, blood clotting
Chapter 19- The Heart
Location- Heart is located in the mediastinum, apex is at tip of left ventricle, base is posterior surface
Pericardium- Membrane surrounding and protecting the heart.
Fibrous Pericardium- tough, inelastic, irregular connective tissue. Serous pericardium- thinner more delicate. Double layer Partiel layer and visceral layer
Layers of Heart Wall- Epicardium- outer layer, Myocardium, Endocardium=inner layer
The heart chambers- 2 atria- recieveing chambers, 2 ventricles- pumping chambers
Right atrium- receives blood from the coronary sinus, vena cava, has fossa ovalis
Right ventricle- blood enters through the tricuspid to the right ventricle go to the pulmonary circuit
Left atrium- receives blood from the lungs
Left ventricle- Recieves blood from the left atrium via mitral valve goes to the systemic circuit
Semilunar valves- aortic and pulmonary valves, valves open when pressure is exceeded.
Coronary circulation- Myocardium has its own network of blood vessels. Coronary veins empty in right atrium.
Cardiac Muscles- autorhythmic fibers-self excitable, act as pacemaker, form conduction system. Contractile fibers-Provide contractions that propel blood.
Conduction system- Begins in Sinoatrial (SA) node, reaches atrioventicular (AV)node enters AV bundle, enters right and left bundle branchesehich extends through interventricular septum toward apex.Purkinje fibers conduct action potential to remainder of ventricle myocardium. Ventricles contract. Nerve impulses from autonomic system and hormones modify timing.
Electrocardiogram- EKG- composite record of action potentials produced by all the heart muscle fibers. 3 recognizable waves- p, QRS, T
Correlation of ECG waves- Systole-contraction/ dystole-relaxtion. Cardiac potential apperars –p wave, Action potential reaches av bundle-QRS wave, repolarization of ventricule fibers- t wave.
Action potential and Contractions- repolarization- recovery of resting membrane potential, refractory period- time interval during which second contraction cannot be triggered, depolarization- contractile fibers have stable resting membrane potential, plateu- period of maintaining depolarization.
Cardiac Cycle- All events associated with one heartbeat. In each cycle, atria and ventricle alternately contract and relax. Forces blood from higher pressure to...
Please join StudyMode to read the full document