Cardiovascular and Resp System PDF

**First Year End Review** **[Cardiovascular/Respiratory System]** **Heart Location: Mediastinum** **Sounds** S1-Closing of the: A/V Valves (tricuspid and mitral valves (bicuspid)) S2-Closing of the:Semilunar valves (Aortic and pulmonary valves) **Phases of the Heart** Systole-Contraction phas...

**First Year End Review** **[Cardiovascular/Respiratory System]** **Heart Location: Mediastinum** **Sounds** S1-Closing of the: A/V Valves (tricuspid and mitral valves (bicuspid)) S2-Closing of the:Semilunar valves (Aortic and pulmonary valves) **Phases of the Heart** Systole-Contraction phase Diastole-Relaxation phase or filling phase **Cardiac Cycle** (Atrial Systole/Ventricular Diastole)....S1\....(Atrial Diastole/Ventricular Systole)....S2 **Frank Starling Law**: The force of cardiac muscle contraction is proportional to the degree of muscle stretch after the filling phase. Degree of stretch can be referred to as the preload. **Conduction system of the Heart** Depolarization starts with the pacemaker which is the SA Node Spreads through the contractile fibers of atria then slows down in A/V node Bundle of His Left and Right bundle branches moves fastest through the Purkinje fibers and finally spreads through contractile fibers of the ventricles Heart has autorhythmicity-Heart has pacemaker that sets its own rhythm independent of Brain and spinal cord. **EKG** P wave-SA node/Atrial depolarization QRS complex-Purkinje/Ventricular depolarization T wave-Repolarization of ventricles **[Systemic Circulation]** **Order of flow**: Left Ventricle Aorta Arteries Arterioles Capillaries Venules Veins Vena Cavas Right Atrium No capillaries in lens of eye; Venous system is considered a reservoir for blood; Remember arteries are high pressure, veins low pressure. **Major arteries** Branches off ascending aorta: Left and right coronary arteries-take blood to heart muscle Branches off arch of aorta: 1. Brachiocephalic trunk(artery)(will split into right subclavian and right common carotid arteries) 2. Left common carotid artery 3. Left subclavian artery 4 arteries that take blood to the brain:Left and right vertebral arteries which will merge into 1 that will be called Basilar artery Left and right internal carotid arteries **Blood Pressure: Pressure in arterial system** Average-Less than 120 (systolic pressure)/ less than 80 (diastolic pressure) Pulse Pressure- Difference between systolic and diastolic pressure. i.e. 120-80=40 **[Blood]** Where are all blood cells produced? Red Bone Marrow; Found in Epiphysis of long bones **Erythrocytes**:RBCs Function:Transport Oxygen and some CO2. Hemoglobin is the molecule that O2 and CO2 attach to. Iron needed to make hemoglobin. Shape:Biconcave Hormone that controls production: Erythropoietin (Made by kidneys)Erythropoiesis(making of RBCs) in red bone marrow **Leukocytes: WBCs** Function: Immunity....protect you from foreign antigens/pathogens, etc Neutrophils: First responders; Most abundant; engage in phagocytosis Eosinophils: Most active in allergies/parasitic invasions Basophils: Make histamine (chemical that causes vasodilation and triggers inflammatory response) Macrophages: Biggest of WBCs; engage in phagocytosis; antigen-presenting cells; It present to the T-Helper cell, which then activates immune response Lymphocytes: Include: 1. T cells and 2. B cells These are the cells of acquired or adaptive immunity: You need that first exposure, but once exposed, you develop very specific, efficient immune response to invader. Humoral Immunity-When exposed to pathogen, B cells mature into plasma cells, which make immunoglobulins (aka antibodies) Cell-Mediated Immunity-Cytotoxic T cells or T killer cells directly attacking and killing infected or diseased body cells **Thrombocytes: Platelets.......initiate coagulation cascade to clot the blood/stop bleeding** **[Respiratory System]** *Order of Parts:* External Nose: Internal Nose: Pharynx:area posterior to nose and mouth.....food and air passes through here. Larynx:Air only; Vocal cords located here; Epiglottis covers the larynx to prevent food from entering Trachea: Bronchi (Primary, Secondary, & Tertiary): Bronchioles: Alveoli:Air sacs where gas exchange occurs; Surrounded by capillaries What is the name of the serous membrane covering the lung? Pleural membrane or pleura. Remember there are 2 layers: 1. Visceral and 2. Parietal How many lobes does the right lung have? 3 Left Lung? 2 What is the function of pulmonary surfactant? Decreases surface tension in alveoli to prevent alveoli from collapsing; Increases lung compliance Internal vs External Respiration: External=gas exchange between atmosphere and blood; occurs in alveoli Internal=gas exchange between blood and body cells Mechanism of external respiration:Medulla oblongata has a group of neurons referred to as the respiratory center, which regulates resp rate and depth. Fires every 5 seconds or so and send action potential down spinal cord to C3, C4, and C5 spinal cord levels. Action potentials then trigger the axons that make up phrenic nerve to fire and phrenic nerve stimulates diaphragm to contract What are the 3 ways we transport CO2 in the blood? -1. Small portion dissolved in plasma -2. Moderate portion carried on hemoglobin molecule -3. 70%(majority) is converted into HCO3- (bicarbonate ion). Used to buffer H+ (buffer acidity)