1. Cardiovascular system ► The heart pumps at approximately 70 times to pump about 5 liters of blood a minute. ► That is about 100,800 times each day. ► In 70 years this amounts to about 2.6 billion beats!

2. Functions ► Nutrients delivered ► Carries away waste ► Transport ► defense ► clotting ► Distributes heat

3. Evolution ► Prokaryotes/protists  Use simple diffusion/active transport/endo & exocytosis  Direct exchange w/ water

4. Evolution cont… ► Open circulatory systems ► Closed circulatory systems

5. Invertebrates ► Cnidarians (hydra, jellyfish)  Gastrovascular cavity  Central canal  Nutrients have only a few layers of cells to diffuse through

6. Invertebrates cont… ► Earthworms(annelids)  Separate digestive system & closed circulatory system  Primitive heart  hemoglobin

7. Invertebrates cont… ► Insects  Open circulatory system ► Hemolymph, hemocoel ► Does not transport O2 ► Long, thin-walled hearts

8. Vertebrate systems ► All have closed circulatory systems ► Strong well-developed hearts ► Capillaries, arteries & veins specialized for delivering blood

9. Vertebrate Hearts ► 2 types of chambers  Atria  Ventricles ► Myocardium ► Pericardium ► Endothelium ► http://www.hhmi.org/biointeractive/animatio ns/heart/heart_middle_frames.htm http://www.hhmi.org/biointeractive/animatio ns/heart/heart_middle_frames.htm http://www.hhmi.org/biointeractive/animatio ns/heart/heart_middle_frames.htm

11. Heart evolution-fish ► Single circulation ► 1 atrium, 1 ventricle  Atrium  vent  gills  cells  veins ► Very low pressure, limited metabolic rate

12. Amphibian heart ► Double circulation ► 3 chambers  2 atria  1 ventricle

13. Reptile Heart ► Double circulation ► 4 chambers-  2 atria, 2 ventricles ► septum

14. Mammalian Heart ► Double circulation ► 4 chambers  2 atria, 2 ventricles ► Highest pressure & metabolic rate

15. http://www-medlib.med.utah.edu/kw/pharm/hyper_heart1.html T Deoxy blood To lungs Deoxy blood from upper body Deoxy blood from vena cava Oxy blood from lungs Pulmonary valve Deoxy blood from lower body Most muscular part Pumps blood to entire body via aorta tricuspid Oxy blood to body Oxy blood from lungs Aortic valve Mitral valve/bicuspid valve

16. Both chambers relaxed Blood fills both chambers “dup” sound as blood slaps against closed SL valves Atria contract, forcing Remaining blood into ventricles Vents contract as SL Valves open Blood forced into aorta & pulm. Arteries “lub” sound as blood slaps Against AV valves The Cardiac Cycle Lub-dup, lub-dup

17. ► Pulse ► Heart rate ► Cardiac output-(liters/min)  Heart rate x stroke volume (Beats/min) (liters/beat) ► 5L/min is avg. ► http://www.wilkes.med.ucla.edu/intro.html http://www.wilkes.med.ucla.edu/intro.html

18. Control of Heart Rhythm 1% of heart cells are autorhythmic Bundle of His

19. P wave Indicates atrial depolarization, or contraction of the atrium. QRS complex Indicates ventricular depolarization, or contraction of the ventricles. T wave Indicates ventricular repolarization