Lecture 15: Introduction to Cardiovascular Flashcards
5 main functions of the cardiovascular system
- Distribution of O2 and nutrients to all tissues of the body
- Transportation of CO2 and metabolic waster products from the tissues to the lungs and excretory organs
- Distribution of water, electrolytes, and hormones throughout the body
- Contributing to the infrastructure of the immune system
- Thermoregulation
Three basic components of the cardiovascular system
- The heart
- The blood
- The blood vessels
The heart serves as a ____ that imparts pressure to the blood to establish
Pump
The pressure gradient needed for the blood flow to the tissues
Blood flows from the area of ___ pressure to an area of ___ pressure
high
low
Heart serves as an ___ ___ because it releases Atrial Natriuretic Peptide from the atria when
Endocrine organ
atrial blood pressure is increased
Atrial Natriuretic Peptide (ANP)
Lowers the blood pressure by increasing the rate of urine production , thus reducing blood volume
The blood serves as
The transport medium within which materials being transported are dissolved or suspended
Blood vessels serve as
the passageways through which blood is directed and distributed from the heart to all parts of the body and subsequently returned to the heart
Endothelial cells line
the inner surface of blood vessles
Important endothelial vasodilators include:
- Nitric oxide
- Prostacyclin
Important endothelial vasoconstrictors include:
- Endothelin
- Thromboxane A2
On the basis of anatomy, the cardiovascular system can be divided into two main circuits:
- Systemic circulation
- Pulmonary circulation
Systemic circulation consists of
Left heart, systemic arteries, capillaries, and veins
Systemic circulation pressure?
High
Where does systemic circulation pump blood?
All organs
Pulmonary circulation consists of
Right heart, systemic arteries, capillaries, and veins
Pressure of pulmonary circulation
Low
Pulmonary circulation pumps blood to
the lungs
The left heart and right heart function in a series so that blood is pumped sequentially from
the left heart to the systemic circulation, to the right heart to the pulmonary circulation, then back to the left heart
Cardiac Output
The rate at which blood is pumped from each ventricle
Venus Return
The rate at which blood is returned to the atria from the vein
Stroke volume
The volume of blood pumped out of each ventricle with each contraction, or beat, of the heart
Systole
Period of cardiac contraction and emptying
Systolic pressure
The highest arterial pressure measured during a cardiac cycle
The pressure in the artery after the blood has been ejected from the left ventricle during systole
Diastole
The period of cardiac relaxation and filling
Diastolic pressure
- The lowest arterial pressure measured during a cardiac cycle
- The pressure in the artery when no blood is being ejected from the left ventricle
Pulse pressure
- The difference systolic and diastolic pressure
- The magnitude of the pulse pressure reflects the volume of blood ejected from the lect ventricle on a single beat
End-diastolic volume (pre-load)
-Volume in the ventricle before ejection
End-systolic volume
-Volume in the ventricle after ejection
Mean arterial pressure (MAP)
The average pressure responsible for driving blood forward into the tissues throughout the cardiac cycle
- MAP = diastolic pressure + 1/3 (systolic pressure - diastolic pressure)
- Monitored and regulated by blood pressure reflexes
After load
-Pressure against which the heart pumps blood
