Unit 1 Lecture Flashcards
What are the three components of the cardiovascular system?
- The heart: which acts as a pump to propel….
- Blood: which moves through tubes called….
- Blood vessels: which conduct blood throughout the body
What does the circulation of blood look like in the heart?
Circulation is continuous with two trips through heart before returning to where you started. The heart is thus often called a double pump.
What is the heart often called?
A double pump
What is each stop at the heart?
Each stop at the heart is the end of a separate circuit
(Heart -> arteries -> capillaries -> veins -> heart)
What are the two cardiovascular circuits?
What does each side of the heart contain?
It contains an atrium and a ventricle. Blood enters into the heart at an atrium and is ejected out of the heart from a ventricle.
Discuss systemic circuit
- Carries oxygenated blood (“arterial blood:) to body cells/tissues/organs
- Begins with the left ventricle of the heart (ejects blood into the aorta) and ends with the right atrium (collects returning blood)
- Distributes blood in a parallel manner. Major recipients of blood include: kidneys, GI system, skeletal muscle, brain, skin, liver, bone, and heart
Discuss the pulmonary circuit (Pulmonary Circulation)
- Carries de-oxygenated blood (“venous blood”) to the lungs where it is reloaded with oxygen (and emptied of excess carbon dioxide) before returning to the heart
- Begins with the right ventricle of the heart (ejects blood into the pulmonary trunk) and ends with the left atrium (collects the returning blood)
- Requires proper functioning of the respiratory system
What does blood flow with?
Blood flows with a concentration gradient
-Blood has more pressure at the start where it is pushed out
Study the circulation of blood
What is cardiac output?
It is the amount of blood pumped by a ventricle per unit time (measured in L/min)
Does the systemic or pulmonary circuit have a faster cardiac output?
Both systemic and pulmonary circuits have the same cardiac output. (Left and right ventricles eject the same amount of blood)
-It is equal to about 5 L/min under resting conditions
Does cardiac output change?
Cardiac output changes to meet the needs of the body. CO can be increased as much as 30 L/min during maximal exercise
What is a heart and what is it composed of?
- Is composed primarily of cardiac muscle
- Is a double pump
- Contains 4 chambers
- Directs blood flow by means of 4 valves
- Is suppled with blood by the first two arteries formed off of the aorta
What are the four chambers of the mammmalian heart? And how does blood move through them?
- Right atrium (RA)
- Left atrium (LA)
- Right ventricle (RV)
- Left ventricle (LV)
What do the atria and ventricles do?
The atria recieves blood; the ventricles force blood out of the heart into systemic and pulmonary circuits
Which ventricle has more muscle and why?
Due to the difference in workload, the left ventricle has much more muscle (is much thicker) than the right ventricle.