The circulatory system carries nutrients and waste throughout the body using the heart and blood vessels. The heart pumps deoxygenated blood to the lungs and oxygenated blood to the rest of the body via a double circulatory system. Arteries take blood away from the heart, and veins carry blood towards the heart and also have valves. The capillaries link arteries and veins and have a one cell thick wall to exchange materials between blood and body cells.

1. Circulatory System

2. What is the circulatory system? The circulatory system carries nutrient and wastes around the body.

3. The Heart and blood vessels together make up theCirculatory System.

4. How does this system work?lungspulmonary arterypulmonary veinhead & armsaortamain veinLeft Rightliverdigestive systemkidneys legs Circulatory System

5. LungsBody cellsOur circulatory system is a double circulatory system. This means it has two parts parts. the right side of the system deals with deoxygenated blood.the left side of the system deals with oxygenated blood.

6. The HeartArtery to Head and BodyArtery to LungsVein from Head and BodyVein from LungsRight AtriumLeft AtriumvalvevalveLeft VentricleRight Ventricle

7. The heart beat begins when the heart muscles relax and blood flows into the atria.How does the Heart work?STEP ONE

8. The atria then contract and the valves open to allow blood into the ventricles.How does the Heart work?STEP TWO

9. The valves close to stop bloodflowing backwards.The ventricles contractejecting blood from the heart.At the same time, the atria areRelaxing again and filling withblood.How does the Heart work?STEP THREEThe cycle then repeats.

10. The ARTERY-carry blood away from the heart.the elastic fibres allow the artery to stretch under pressurethick muscle and elastic fibresthe thick muscle can contract to push the blood along.

11. The VEINVeins carry blood towards the heart.veins have valves to stop the blood from going in the wrong direction.thin muscle and elastic fibresbody muscles surround the veins so that when they contract they squeeze the veins and push the blood along the vessel.

12. The CAPILLARYCapillaries link Arteries with Veinsthey exchange materials between the blood and other body cells.the wall of a capillaryis only one cell thick

13. SUMMARYArteries take blood ______ from the heart. The walls of an artery are made up of thick _________ walls and elastic fibres. Veins carry blood ________ the heart and also have valves. The _________ link arteries and veins, and have a one cell thick wall. awaymusculartowardscapillaries

14. Heart BeatMeasure in bpm, beats per minute. Specialised tissues produce electrical signals which flow down through the heart, causing the atria to contract, then the ventricles.

15. ECG - Electrocardiogram Used for diagnosis.

16. Normal sinus rhythm Between 60 and 100 bpm Regular electrical signal that stimulates rhythmic contractions of the cardiac muscle

17. BradycardiaBrady=Slow<60bpm

18. PacemakerHelps heart keep pace if heart rhythm is too slow

19. TachycardiaTachy = Fast>100bpm

20. Atrial FibrillationErratic electrical signals prevent the atria from relaxing (filling) and contracting (ejecting)

21. Ventricular FibrillationErratic electrical signals prevent the ventricles from relaxing and contracting. Can be lethal in minutes! An electric shock is required to restore normal rhythm.

22. Defibrillator

23. Implantable Defibrillator Sends an electric shock directly into the heart. Restores normal sinus rhythm if in ventricular tachycardia or ventricular fibrillation.