Circulatory System Flashcards
Stroke volume
- The volume of blood pumped from one ventricle of the heart in a single pump (healthy individuals have the same stroke volume for both ventricles)
- SV = EDV - ESV
- EDV = volume of blood in ventricle before contraction
- ESV - volume of blood in the ventricle at the end of the contraction
Activated thrombin converts:
Fibrinogen to fibrin
What does the Q wave of electrocardiogram represent?
Depolarization through the interventricular septum (which initiates ventricular depolarization)
What are known as capacitance vessels?
Veins because of their high capacity —> most of the body’s blood is found in veins
Pulmonary circulation:
Moves deoxygenated blood to the lungs in order to become oxygenated
The pathway is as follows:
Superior/inferior vena cava —> right atrium —> tricuspid valve —> right ventricle —> pulmonary semilunar valve —> pulmonary arteries —> lungs —> pulmonary veins —> left atrium
Which blood do cardiac veins carry?
Deoxygenated blood from the myocardium
What does thromboplastin convert?
Prothrombin (inactive precursor) to thrombin (active form)
Automaticity
A property of all cardiomyocytes, allowing cardiomyocytes to have the ability to generate action potentials without external nerves having to initiate the action potential
Cardiac output
- volume of blood being pumped by the heart (ventricle) in one minute
CO = HR x SV
What do activated platelets release?
Thromboplastin (also called a tissue factor)
How to calculate mean arterial pressure
MAP = CO x TPR
Cardiac output from the heart multiplied by the total peripheral resistance of the vessels
What is another name for the respiratory pump?
Abdominothoracic pump because it involves both the abdomen and the thoracic cavity
Hemolymph
Functions as both blood and interstitial fluid in organisms that contain an open circulatory system
It contains nutrients (similar to blood) and lies between cells (similar to interstitial fluid)
Sinuses
- found in organisms with open circulatory systems (arthropods)
- Small, open-ended chambers that hemolymph move into form the dorsal vessel
Hemocoel
A large cavity (body cavity) that surrounds all of the internal organs of the insect where sinuses empty hemolymph into
It allows for the hemolymph to surround and nourish all of the organs
Ostia
Openings in the tubular hearts in which hemolymph can re-enter the relaxed heart and go back to the dorsal blood vessels
It does so by locomotion and muscular contractions
Spiracles
Tiny holes that allow air to pass into the tracheal tubes/system (act as nostrils)
Tracheal system
(Act as lungs) Responsible for gas exchange between the insects cells (the hemolymph) and the environment
Which circulation has a higher resistance to blood flow?
Systemic circulation