Cardio System(A&P) Flashcards
Heart
- slightly larger than an adults fist
- located in thoracic cavity within the mediastinum
- shaped like a cone:
base: superior margin to which the great vessels are attached
apex: pointed left and down - point of maximal impact is at the level of the 5th intercostal space, midclavicular on the left side
Pericardium(covering)
- covering the heart
- fibrous pericardium
- serous pericardium
1. parietal layer
2. serous fluid(pericardial fluid)
3. Viceral layer(epicardium)(heart wall)
Endocardium(inner layer of heart wall)
- visceral layer of the serous pericardium
- squamous epithelieum cells and connective tissue
- rough surface promotes blood clotting
Myocardium(middle layer of heart wall)
- compose of cardiac muscle
- responsible for pumping blood
- made up of cardiac muscle cells
- striated slightly
- mononuclieated
- connected two each other by intercalted disc
- involuntary control
- sets its own rhythmn
Epicardium(outer layer of heart wall)
-contains visceral layer of the serous pericardium
Partition of the Heart(Septum)
- heart is a pump, double pump
- divided into two separate pumps by the septum(myocardium)
- right side=recieves and pump deoxygenated blood
- left side=recieves and pumps oxygenated blood
Atria(chamber of the heart)
- recieve blood
- atria upper chamber
- recieve blood entering the heart and pumping into ventricles
- atria had thin walls
Right atrium
- recieve blood returning from the body(deoxygenated)
- two major blood vessels return blood to the atrium superior and inferior vena cava
Left atrium
- recieves blood returning from the lungs(oxygenated)
- blood return from lungs to heart by 4 pulmonary veins
Ventricles(pump blood)
- two lower chambers
- pump blood out of the heart
- they have thick walls
Right Ventricles
- receives blood from the right atrium
- pumps into the pulmonary trunk
- which divides into right and left pulmonary artery
Left Ventricles
- thicker walls thank right ventricles
- recieve blood from left atrium
- and pump itout into the aorta
Valves of the Heart
- heart valves provide for one way blood flow
- Right AV valve
- Left AV valve
- Aortic SL valve
- Pulmonary Sl valve
Right Atrioventricular Valve: Tricuspid Valve
- open when right atrium contracts
- close when right ventricle contracts
Pulmonic Valve: Semilunar Valve
- located btw right ventricle and pulmonary trunk
- opens when right venticle contracts
- closes when right ventricle relaxes
Left Atrioventricular Valve: Bicuspud: Mitral Valve
- open when left atrium contracts
- close when left ventricle contracts
Aortic valve: Semilunar valve
- located btw left ventricle and aortic
- open when left ventricle contracts
- close when left ventricle relax
Cardiac Cycle
- sequence of events in one heart beat
- blood is constantle flowing in from the veins into the atria
- atrial systole followed by ventricular systole
Cardiac Cycle
1-the atria are relaxed and fill with blood(blood flows passively into the ventricles)=atrial dystole
2-atrial contraction pumps the remainging blood into the ventricles=atrial systole
3-ventricle contraction(the atria are relaxed) pumps blood into the arteries(the AV valves close and the SL valves open)=ventricular systole
4-ventricular relaxation-ventricles are filling up with blood(SL valves close and the AV valves open)=ventricular dystole
Cardiac output
- amount of blood pumped by each ventricle in one minute
- stoke volume x hour
- 5-6L/min
- varies to meet the body demand for 02
Factors that affect cardiac output
1) Stroke volume: volume of blood pumped by each ventricle w/ each heartbeat(cardiac cycle)
2) preload: amount of blood in the ventricle at the end of diasytole
3) Afterload:pressure(resistance) ventricle overcomes to eject blood into the artery(vascular resistance)
4) contractility: strength of contraction of the myocardium
Conduction system of the Heart
1) SA Node
2) AV Node
3) BOH
4) R/L bundle branches
5) Purkinjie Fibers
SA Node: Sinoatrial Node
- specialized mass of tissue that initates the signal for each heart beat
- located in the upper wall of the right atrium
- sets the normal rate of heart contractions(normal sinus rythmn) 60-100
- called the pacemake of the heart
AV node: Atrioventricular Node
- located at the top of the intraventricular septum
- recieves the signal from the SA nose and delays conducting it usually until the end of the atrial systole
- transmits the signal to the BOH
- can initate the signal for heart beats if the SA node is damaged but at a lower rate(40-60)
Bundle of HIS
- bundle of conducting fibers that travels through the top part of the intraventricular septum
- AV bundle seperate into the R/L Bundle
- The Right bundle goes to the right ventricle
- the left bundle goes to the left ventricle
Purkinjie Fibers
-transmits electrical signal to the ventricular myocardial
Pathway of conduction
1)SA node fires(generates impulse)(starts heart beat)
2A)impulse travels to the atrial myocardial and atrial contract
2B)impulse travels to the AV node
3)at the end of the atrial contraction the AV node transmits the signal to the BOH
4)impulse travel through the BOH to the right and left bundle branches to the purkinjie fibers to the ventricle myocardium and the ventricle contract
Stimulation of the Heart
- medulla oblongata had two cardiac center
- accelerator center provides sympathetic stimulation
- inhibtory center provides parasympathetic stimulation via the vagus nerve(or nerve x)
Bradycardia
-slow, below 60
Tachycardia
-fast. above 100
Blood vessels
- 3 layers
- outer-connective tissue
- middle layer-smooth muscle
- inner-simple squamouse epitheliuem-smooth surface for blood flow
Arteries
- carry blood away from the heart
- thick layer of smooth muscle in the wall
Arterioles
-artery w/ small diameter
Capillaries
- exchage vessels
- have extremely thin walls
- allow diffusion of 02 and nutrients into tissue
- diffusion of waste product from tissue to bloodstream
Venules
smaller in diameter to veins
Veins
thick layer of connective tissue
-think layer of small muscler
have semilunar vavles to prevent backflow
-skeletal muscle pump prevent backflow
-resp pump when inhale chest expand, exhale relax
circulation
- divided into 2 major pathways
- pulmonay
- systemic
Pulmonary circulation
- delivers deoxygenated blood to lungs where gas exchange occurs
- 1) RA_Tricuspid Valve_RV_Pulmonary Valve_Pulmonary Trunk(R/L Pulmonary Artery)_R/L Lung_4 pulmonay veins
Systemic circulation
- delievers blood/oxygen to the entire body
- 1)LA_mitral/bicuspid valve_LV_aortic valve_Aorta_Upper/lower extremeties_sup/infer vena cava_RA
Aorta
- largest artery in the body
- carries oxygenated blood from the left ventricle
- 3 parts
- ascending aorta=coronary arteries
- aortic arch(arteries that supply the head and upper extremities) curves to the left and back of the head
- several arteries branch off the aortic arch they go to feed the head,neck,upper extremities
- descending aorta=arteries that perfuse thoracic,abdomen,lower extremities
- descending aorta part that travels posterior to heart through thoraic through diagphram through abdomen
vena cava
- two major veins that return blood to the heart
- return blood to the right atrium
- superior vena cava returns blood from head,neck,upper extremities to the tright atrium
- inferior vena cava returns blood from thorasic,abdomen,lower extermeties to right atrium
coronary circulation
- goes to the myocardium
- feeds the heart
- branches off the aorta
- supplies the myocardium
- right and left coronary arteries are the first branches from the ascending aorta
- blood is drained from the heart by the coronary sinus which opens into the right atrium
Hepatic portal circulation
- blood that is rich in nutrients leave the stomach, pancreas and intestines(both small and large) and passes through the liver before it reaches the inferior vena cava on its way back to the heart
- hepatic portal vein
- liver detoxifies toxins and processess and stores nutrients-(first pass effect)
Physiology of circulation
- blood pressure-force exerted by the blood against the walls of the blood vessels
- factors that affect blood pressure
- blood volume
- cardiac output
- resistance to flow
- blood vessels elasticity
pulse
- a heart beat tjat is palpated at a peripheral arterial site
- artery has to be superficial and cross firm tissue
- common sites for palpating pulses: radial,femoral,temporal,common cartoid,popliteal
- dorsal pedis: over arch of feet
- posterior tibial =side of feet
- must assess rate,regularity,and strength
Function of blood:
Transportation
-blood transport oxygen,nutrients,electrolytes,vitamins,hormones,to body tissues,removes co2, and metabolic waste from the body tissue and transports it to specific organs for excretion
Function of blood:
Regulation
- blood regulates PH of body tissue because it contains buffers
- normal blood ph: 7.35-7.45
- normal blood temp: 38c/100.4F
- regulate body temo, absorb heat from skeletal muscle and circulates it
- regulation of fluid content of various tissues
Function of blood:
Protection
- protection against disease
- inflammation
- blood clotting=prevents hemorrage from a vessel that is cut
characteristic of blood
- viscous fluid connective tissue which varies in color from bright red to dark red
- total blood volume= 5-6 liters in males, 4-5L in females
- liters x 2 =pint
- blood is 8% of our body weight
plasma
- straw colored,sticky fluid
- mostly water
- has many solutes: nutrients,gases,hormones,waste,ions,proteins
- serum is plasma from which clotting proteins are removed
- most plasma proteins are produced by liver
Components of blood
- plasma= 55%
- leukkocytes= less than 1%
- erythrocytes=45%
proteins(ALBUMIN)
- important plasma protein
- most abundant protein
- acts as carrier for other molecules
- buffers the blood
- major contributor to blood osmotic pressure(which keeps water in blood vessels and keeps from leaking out into tissue
- sodium ions also contribute to osmotic pressure
proteins(Antibodies)
-produced by plasma cells(B lymphocytes) in response to specific antigens and play a major role in immunity
proteins(blood clotting factors=Fibrinogen and Prothrombin)
- proteins that are produced by the liver that cause coaguation
- ex: fibrinogen/prothrombin
Regulatory substances(components of blood)
-hormones and enzymes
Nutrients(components of blood)
-glucose,amino acids,fatty acids
Electrolytes(components of blood)
-ions(na,K,Ca,Mg)
Respiratory gases(components of blood)
-o2/c02
Nitrogenous wastes(component of blood)
-metabolic wastes
Formed Elements
- Erythrocytes
- eukocytes
- Thrombosytes
RBC-Erythrocytes
- normal count: 4.4-5million/Ul
- HGB=g/dL=14-17(male) 12-15(female)
- HCT=%=43-54(male) 36-46(female)
RBC(Function)
- transports 02 bound to hemoglobin
- hemoglobin transports some C02
- hemoglobin acts as a buffer
RBC(Characterisitcs)
- most numerous blood cell(5mil per ml)
- bi concave disk w/o nuclei
- contain large amounts of hemoglobin(the 02 carryier)
- lifespan of 120days(4months)
- erythropoiesis occurs in the bone marrow
- production is stimulated by the hormone erythropoietin(produced by the kidney in response to tissue hypoxia)
Leukocytes(WBC)
- round cell with large nuclei
- classified according to characterisitcs of nucleus
- life span=few hrs to few days
Leukocytes(WBC) FUNCTION
- protective
- destroy pathogens
- produce antibodies
- clean the body of foreign material and tissue debris
Leukocytes(WBC) Characteristics
- normal count: 5,000-10,000cells/ml
- multiply during acute infection
- so a count greater than 12,000 is indivative of infection
Leukocytes(WBC) Classification
1) granulocytes:
- neutrophils: phagocytes(first respond to infection)
- Esoinophils:allergic reaction and defense against parasites
- Basophils: allergic reaction and inflammation
2) Agranulocytes:
- Lymphocytes: T-cells and B-cells
- Monocytes: Macrophages
granulocytes
- neutrophils: phagocytes(first respond to infection)
- Esoinophils:allergic reaction and defense against parasites
- Basophils: allergic reaction and inflammation
Agranulocytes:
- Lymphocytes: T-cells and B-cells
- Monocytes: Macrophages
Platelets(Thrombocytes)(Functions)
- essential in blood coagulation
- help to repait damaged blood vessels
Platelets(Thrombocytes)(characteristics)
- cell fragment of a megakaryocyte
- normal count: 150,000-450,000
- lifespain 5-9days
Hemostasis
- stopping of bleeding
- injury causes rupture of blood vessels
- vascular spasms=to reduce blood loss,triggered by injury,pain,chemicals
- platelet plugformation: seal damaged blood vessels
- platelets become sticky when exposed to a rough surface
- coagulation-series of reactions the end of which the production of fibrin, tough insoluble protein, forms part of the blood clot(along w/ platelets)
- prothrobin + Ca=thrombin
- thrombin + firbrinogen=fibrin
- fibrin + platelet plug=clot
coagulation-series of reactions the end of which the production of fibrin, tough insoluble protein, forms part of the blood clot(along w/ platelets)
- prothrobin + Ca=thrombin
- thrombin + firbrinogen=fibrin
- fibrin + platelet plug=clot
Blood Group-types
-blood types is determined by the antigens(tiny markers that are present on the surface of cells) on the rbc of the body
-for medical purposes there are two major antigen classifications system
-ABO system and RH System
-
Blood group type
- four different blood types according to the ABO system
- Type A has A antigen on the surface of the RBC and makes anti B antibodies
- Type B has B antigens on the surface if the RBCs and makes anti A antibodies
- Type AB has A and B antigens on the surface of the RBC and does not make anti A or Anti B antibodies
- Type O has neither A and B antigen on the surface of the RBC and makes both Anti A and Anti B antigen
Type A
- Anti-A on the surface of the RBC
- makes anti B antibodies
Type B
- has B antigens(ANTI B) on the surface if the RBCs
- makes anti A antibodies
Type AB
- AB has A and B antigens on the surface of the RBC
- does not make anti A or Anti B antibodies
Type O
- has neither A and B antigen on the surface of the RBC
- makes both Anti A and Anti B antigen
Lymphatic Circulation
- not a circuit/circle
- starts in tissue ends with lymph joining the blood stream components
- lymph capillary=ends of lymph capillary are open, walls of lymph capillaries are more permeable
- lymph capillaries join together to form lymph vessels, lymph vessels have thinner walls than blood vessels
- lymph vessels join to form lymph ducts, ducts empty/drain into the right/left subclavian vein
Lymph nodes
- scattered along the length of the lymph vessels
- found in groups
- filter lymph
- areas where lymph multiply and attack pathogens
Tonsils
- remove contaminents on the body
- remove if frequent injections
Adenoids
-located in nasopharynx behind the nose
Palatine Tonsils
-located in oral phaynx on either side of the soft palate
Lingual Tonsils
-located at base of tongue
Thymus
- located at base of neck top of chest
- plays role in immunity
- hormone: thymosine: mature multiply T cells
- shrinks with age
Spleen
- larger lymphatic organ
- located in left hypochondriac region below the diaphragm
- has huge blood supply
- contains phagocytes and lymphocytes
Spleen(function)
- filter blood removes impurities and cell debris
- destroys old red blood cells
- produces red blood cells before birth
- serves as a reservoir for blood
- spleen gets blood from the hepatic portal circulation
- Fe(Iron) from old rbc goes to liver
appendix
-lymphatic organ whose function we do not know
RH system
- helps place people in 2 different blood types(RH positive and RH negative)
- antibodies are not present prior to first exposure
- positive has Rh negative doesnt
