IS2 Circulation PPT
- 1. Why do we need a transport system?IS2
- 2. FunctionsTransport nutrients, hormones and oxygen throughout the bodyCarry waste away from cells (ex. CO2, urea)Protect body from infection (it transports antibodies and white blood cells)
- 3. Parts of Cardiovascular SystemHeartBloodBlood VesselsArteriesCapillariesVeins
- 4. Heartmuscular pump located between your lungs. a sac called pericardium encloses the heart. 4 chambers:the two upper chambers, which receive blood returning to the heart, are called atria (singular, atrium). the two lower chambers are called ventricles, which pump blood out of the heart.
- 5. Valvesflaps of tissue that prevent blood from flowing backwardslocated between the atria and ventricles and between the ventricles and the arteries leading from the heartthe opening and closing of the valves cause the “bump bump” sound of the heart.
- 6. Blood Flow: 2 circuits/loopsPulmonary Circuit carries oxygen-depleted blood from the heart to the lungs and oxygen-rich blood back to the heart.
- 8. Systemic Circuitcarries oxygen-rich blood from the heart to the rest of the body and oxygen-depleted blood back to the heart.
- 9. Heart->Body ->HeartBlood VesselsArteries: take blood (with high pressure) Away from the heart =thick walls: help withstand high pressuremore smooth muscle: help pump blood, make the vessel more elasticsmall space inside (increases pressure)Veins: take blood (with low pressure) back to the heartthinner walls compared to arteries: less smooth musclehave valves to prevent backflow of bloodlarge space inside (decreases pressure)Capillaries: connect arteries and veins/allow exchange of substances between blood and tissuesmicroscopic: only one cell at a time can go through themsingle-celled wall: allows easy diffusion of substancesreach every cell in the body
- 10. Diffusion between cells and vessels
- 11. PacemakerGroup of cells in the right atrium that can produce a contraction
- 12. Contraction stimulus is picked up by nerve cells and spread to the rest of the heart Nerves and HormonesThe pacemaker is controlled by:nervous systemopposing nerves control the pacemaker by speeding it up and by slowing it down. endocrine systemhormones secreted into the blood also control the pacemaker. hormone epinephrine, also called adrenaline, increases heart rate when the body is under stress.
- 13. Bloodconnective tissue made up of cells and liquid. blood is pumped through the body by the heartyou have about 4-6 liters of blood it takes about 1 min for blood to make a complete circuit through the body.
- 14. Blood CompositionPlasma is 90% water. The other 10% contains: dissolved salts, proteins, hormones, CO2, antibodies, urea, sugar, etc...RedBloodCellsCarryoxygento thecellsContainhemoglobin, a proteinthatstoresoxygen (hemoglobincontains IRON)White BloodCellsProduceantibodies + destroypathogens = fightinfectionsPlateletsSmall fragmentsofcellsthathelp stopcutsfrombleedingRelease clottingfactorsthathelp formprotein threads calledfibrinFibrin threads trapplateletsandbloodcells to make a bloodclot.
- 15. Blood PressureconsistsoftwonumbersSystolicPressureproducedwhentheventriclescontractDiastolicPressureproducedwhentheheart relaxesaveragebloodpressure for healthyadults120/80(120 over 80)averageheart rate is about 70 beats per minute
- 16. Atherosclerosisslow build up of plaque (lipids, cholesterol)insidevesselsarteries become harder, less flexibleless space for bloodif coronary arteries are affected: heart attack might happen = heart cells dieFactors affecting coronary heart disease (CHD):Age, race, heredity, gender, cholesterol levels, blood pressure, obesity, diabetes, smoking, sedentary lifestyle, stress
- 17. HealthCholesterol /fats might clog arteries = pressure inside vessel increases = hypertension/even heart attackSalt also promotes hypertensionRegular exercise makes the heart strongerSmoking increases blood pressure (nicotine is a stimulant = increases heart rate/tar accumulates all over lungs = make gas exchange more difficult/CO stick to red blood cells permanently)