Physiology of the Cardiovascular System Flashcards
components of the cardiovascular system diagram
Components of the cardiovascular system:
- cardiopulmonary unit
- left side and right side
- pulmonary artery and vein
- arteries, arterioles, capillaries, venules and veins
- portal systems: hepatic portal system and hypopyseal ( connects hypothalamus with anterior pituitary)
- intra-renal circulation
- intra-cranial circulation
- intra-coronary circulation
Hypophyseal
a system of blood vessels in the microcirculation at the base of the brain, connecting the hypothalamus with the anterior pituitary. Its main function is to quickly transport and exchange hormones between the hypothalamus arcuate nucleus and anterior pituitary gland.
State the 2 overall functions of the cardiovascular system:
- rapid convective transport of substances
- homeostatic control
Overall functions of the cardiovascular system: rapid convective transport of (6): Name three examples.
- O2
- glucose
- amino acids and fatty acids
- vitamins
- water
- waste products of metabolism: CO2, urea, creatine
Overall functions of the cardiovascular system: Homeostatic control:
- hormones
- temperature
Stroke Volume
the volume of blood pumped by the left ventricle per beat
Cardiac Output
stroke volume x heart rate
the volume of blood pumped by the heart per unit time
measured as L/minute
Perfusion
the passage of blood through the circulatory system to the body’s tissues
measured as ml of blood per minute per gram of tissue
Preload (cardiovascular):
- definition
- measured
- denoted
the degree to which the bentricles are filled at the end of diastole, just prior to systolic contraction
measured as end-diastolic volume in mL
denoted by EDV
Contractility (cardiovascular):
- definition
- measured
- denoted
the innate ability of the myocardium to contract
Afterload (cardiovascular):
- definition
- measured
- denoted
the resistance (increases if blood is thicker or vessels is affected) against which the left ventricle must eject the stroke volume from the heart
measured as aortic pressure during systole divided by cardiac output
Compliance (cardiovascular):
- definition
- measured
- denoted
- the ability of a blood vessel to expand and contract with changes in pressure
- measured as unit of volume change per unit of pressure change
- denoted by c
Factors affecting heart rate
Factors affecting Stroke Volume
Factors affecting Cardiac Output
Factors affecting Stroke Volume
Frank-Starling Mechanism
The stroke volume of the heat increases in response to an increase in the volume of blood in the ventricles before contraction, when all other factors remain constant
Frank-Starling Mechanism
Pressure Volume Diagram
Extrinsic Control of circulation:
- autonomic vasomotor nerves:
- sympathetic vasoconstriction
- parasympathetic vasodilation
- sympathetic vasodilation - Renin-Angiotensin- Aldosterone
- Adrenaline
- Anti-diuretic hormone/ arginine
vasopressin - natriuretic peptides
- other hormone control
- sensory nerve vasodilation
Autonomic Nervous System