Physiology Ch. 15 CARDIOVASCULAR SYSTEM - BLOOD FLOW THROUGH THE HEART Class Notes Part 2
Valves
- 2 A-V valves - 2 S-L valves
Blood Flow thru heart starting at Superior and Inferior Vena Cava
-Superior/Inferior vena cavae -To R.A. -To Tricuspid Valve -To R.V. -To Pulmonary semilunar valve -To Pulmonary Trunk -To Pulmonary arteries -To Lungs - pick up O2 -To Pulmonary Veins -To L.A. -To Bicuspid (mitral) valve -To L.V. -To Aortic semilunar valve -To Aorta -To All Body Tissues - drop off O2 -Back to Superior and Inferior Vena Cava
From the lungs to the heart FYI
1. After blood is refreshed with oxygen, it's bright red. 2. Then it returns to left heart through the pulmonary veins to left atrium. 3. From there left atrium is systole (contracts) it passes through the Atrioventricular A-V valve and enters left ventricle (diastole).
Step 1 From the body to the heart. FYI
1. Dark bluish blood, low in oxygen, flowing back to the heart after circulating through body. It returns to heart through veins and enters right atrium. 2. Atrium contracts (systole) pushing blood into ventricle (diastole) thru open A-V valve
From the heart to the body FYI
1. Left ventricle (systole) pumps the red oxygen-rich blood out through semilunar S-L valve into aorta. 2. The aorta takes blood to the body's general circulation.
Heart attack causes
1. Myocardial Infarction - MI - portion of the heart is deprived of oxygen due to blockage of a coronary artery 2. Cut off blood flow thru coronary arteries
Step 2 From the heart to the lungs FYI
1. Right ventricle (systole) pumps blood through open semilunar S-L valve into pulmonary artery. 2. Then blood goes to lungs where it gets fresh oxygen.
Blood Flow thru heart starting at Superior and Inferior Vena Cava (picture)
1. Superior and Inferior Vena Cava 2. R.A. 3. Tricuspid Valve 4. R.V. 5. Pulmonaary semilunar valve 6. Pulmonary Trunk 7. Pulmonary arteries 8. Lungs - pick up O2 9. Pulminary Veins 10. L.A. 11. Bicuspid (mitral) valve 12. L.V. 13. Aortic semilunar valve 14. Aorta 15. All Body Tissues - drop off O2 THEN Back to Superior and Inferior Vena Cava
Cardiac Cycle Part 2
Aterm-13fter blood is in ventricle- -Ventricular systole & pumps blood into aorta -Atrial is Diastole (relaxed) *Atrioventricular A-V valves closed and Semilunar S-L valves are open
In Cardiac Cycle, Atrial Systole
Atrial Contraction
In Ventricular Systole, Atrial Diastole
Atrial Contraction
Cardiac Cycle Part 1
Atrial systole (contraction) (pumps blood) into Ventricular diastole (relaxation) *Atrioventricular A-V valves are open and *Semilunar S-L valves are closed.
Two A-V Valves (Antrial Ventricular)
Attached to heart muscle by Chordae tendineae
Two S-L Valves (Semilunar Valves)
Attached to heart muscle by Chordae tendineae
Systole
Contraction
Blood supply to heart muscle
Coronary Arteries Coronary Veins
Diastole and Systole of the Heart (FYI)
FYI - SYSTOLE: The period of contraction that the heart undergoes while it pumps blood -DIASTOLE: The period of relaxation that occurs as the chambers fill with blood -Both atria and ventricles undergo Systole and Diastole
Blood flow
It is a cycle that flows: Body-Heart-Lungs-Heart-Body.
Valves opening & closing - the sounds of the heart
Lub: A-V (Atrioventricular) valves closing Dub: S-L (Semilunar) valves closing
Function of Valves
Prevent backflow of blood
Diastole
Relaxation
Coronary Veins
Return low O2 blood from heart muscle
Coronary Arteries
Supply high O2 blood to heart muscle
Atrial Systole and Ventricular Diastole
The atria begin to contract (atrial systole) and pump blood into the ventricles (diastole). The ventricles begin to contract (ventricular systole), to push blood out. The valves prevent backflow of blood.
Parts of the heart
The heart has four chambers. The upper two chambers are the atria, and the lower two are the ventricles. The chambers are separated by a wall of tissue called the septum. Blood is pumped through the chambers, aided by four heart valves.
In Atrial Systole, Semilunar Valves
Valves are Closed
In Ventricular Systole, A-V valves
Valves are closed
In Atrial Systole, Atrioventricular Valves (A-V)
Valves are open
In Ventricular Systole, Semilunar valves
Valves are open
In Atrial Systole, Ventricular diastole
Ventricular Relaxation
