internal structure:
external structure of heart: • atria: t wo upper chambers blood flow through the heart
• found in middle of thorax • ventricle: t wo lower chambers
• slightly to left • septum: muscular wall separating 1. deoxygenated blood from body
• pericardium: double membrane (fluid left and right sides of heart 2. inferior and superior vena cava
bet ween to prevent friction) • right side: deoxygenated blood 3. right atrium
• cardiac muscle • left side: oxygenated blood 4. tricuspid valve
• coronary blood vessels: supply • atrioventricular valves: valves 5. right ventricle
heart with blood bet ween atrium and ventricles 6. leaves heart
• tricuspid: right 7. pulmonary valve
• bicuspid: left 8. lungs
superior vena cava pulmonary artery
9. oxygenated
·
gen · left atrium
10. heart
·
aorta
-
I
⑭IM
·
pulmonary veins 11. pulmonary veins
transport systems in mammals 12. left atrium
-
*·
↑
E
·
right atrium
left ventricle
13. bicuspid valve
↑
coronary vessels
14. left ventricle
right ventricle
double circulation 15. aortic valve
• pulmonary circulation: 16. aorta
superior vena cava
heart to lungs to heart 17. oxygenated
aorta • systematic : heart to
s body back to heart
og&
right atrium pulmonary artery
g
Blood circulation systems
↑.....
...
=
ot
· (AD
·
pulmonary veins
*
left atrium
3 main parts:
closed circulatory system • blood - the fluid in which
⑲
e
bicuspid valve
• blood confined to vessels
tricuspid valve
e left ventricle
• in most animals
substances flow from one
pulmonary valve
↳ area of body to another
muscular wall
• heart pumps blood around body • blood vessels - tubes in
right ventricle aortic valve
inside vessels (blood returns to which blood circulates
heart) • heart - pumps to circulate
fluid
, the cardiac cycle: a heart beat
1. atrial systole
2. ventricular systole I heart muscle contracts
3. general diastole heart muscle relaxes
general diastole
atrial systole ventricular systole • 0,4 seconds
• 0,1 seconds • 0,3 seconds • heart relaxes
• atria contract • ventricles contract • valves close
• blood vessels constrict blood flow • blood leaves heart • blood enters
mechanism controlling heart beat
1. lower blood pressure
heart undergoes series of electrical changes during cardiac cycle 2. sympathetic nerve sends impulse
3. sinoatrial node stimulating
sinoatrial node : 4. atria contract
• where heart beat begins 5. stimulates atrial ventricular
• netural pace maker node
• in wall of right atrium 6. ventricles contract
• attached to brain by sympathetic snd parasympathetic ner ve 7. heart beats faster
8. higher blood pressure
9. parasympathetic nerve lowers
HR
speeds up HR returns HR to normal
adrenaline: hormone stimulating sympathetic nerve - increases heart rate
external structure of heart: • atria: t wo upper chambers blood flow through the heart
• found in middle of thorax • ventricle: t wo lower chambers
• slightly to left • septum: muscular wall separating 1. deoxygenated blood from body
• pericardium: double membrane (fluid left and right sides of heart 2. inferior and superior vena cava
bet ween to prevent friction) • right side: deoxygenated blood 3. right atrium
• cardiac muscle • left side: oxygenated blood 4. tricuspid valve
• coronary blood vessels: supply • atrioventricular valves: valves 5. right ventricle
heart with blood bet ween atrium and ventricles 6. leaves heart
• tricuspid: right 7. pulmonary valve
• bicuspid: left 8. lungs
superior vena cava pulmonary artery
9. oxygenated
·
gen · left atrium
10. heart
·
aorta
-
I
⑭IM
·
pulmonary veins 11. pulmonary veins
transport systems in mammals 12. left atrium
-
*·
↑
E
·
right atrium
left ventricle
13. bicuspid valve
↑
coronary vessels
14. left ventricle
right ventricle
double circulation 15. aortic valve
• pulmonary circulation: 16. aorta
superior vena cava
heart to lungs to heart 17. oxygenated
aorta • systematic : heart to
s body back to heart
og&
right atrium pulmonary artery
g
Blood circulation systems
↑.....
...
=
ot
· (AD
·
pulmonary veins
*
left atrium
3 main parts:
closed circulatory system • blood - the fluid in which
⑲
e
bicuspid valve
• blood confined to vessels
tricuspid valve
e left ventricle
• in most animals
substances flow from one
pulmonary valve
↳ area of body to another
muscular wall
• heart pumps blood around body • blood vessels - tubes in
right ventricle aortic valve
inside vessels (blood returns to which blood circulates
heart) • heart - pumps to circulate
fluid
, the cardiac cycle: a heart beat
1. atrial systole
2. ventricular systole I heart muscle contracts
3. general diastole heart muscle relaxes
general diastole
atrial systole ventricular systole • 0,4 seconds
• 0,1 seconds • 0,3 seconds • heart relaxes
• atria contract • ventricles contract • valves close
• blood vessels constrict blood flow • blood leaves heart • blood enters
mechanism controlling heart beat
1. lower blood pressure
heart undergoes series of electrical changes during cardiac cycle 2. sympathetic nerve sends impulse
3. sinoatrial node stimulating
sinoatrial node : 4. atria contract
• where heart beat begins 5. stimulates atrial ventricular
• netural pace maker node
• in wall of right atrium 6. ventricles contract
• attached to brain by sympathetic snd parasympathetic ner ve 7. heart beats faster
8. higher blood pressure
9. parasympathetic nerve lowers
HR
speeds up HR returns HR to normal
adrenaline: hormone stimulating sympathetic nerve - increases heart rate
