Chapter 21 pt. 2 Flashcards
Volume of blood flowing through a vessel, organ, or body per unit time (ml/min)
Blood Flow
The force exerted on the walls of vessels by the blood(mmHg)
Blood Pressure
Pressure gradient, generated by contraction of ventricles, and dependent on volume of blood
Blood Pressure
Thickness of blood
Blood Viscosity
Dehydration can or cannot change the relatively constant source of resistance?
Can change it
As length of blood vessels increase, the resistance _______.
Increases
Most important factor in determining resistance is ______ _______
Blood vessel diameter
Constricts and relaxes to change blood flow and therefore not constant
Blood vessel diamter
Cross sectional area is ________ at capillaries.
greatest
Decreases with increase in cross sectional area.
Velocity of flow
_______ depends on how much elastic arteries can be stretched, blood flow, and is not constant due to heartbeat.
Arterial Pressure
Low pressure required in capillaries because __________
Capilaries are thin walled
BP drops to 35-40mmHg before entering ______ and drops to 20mmHg at end
Capillaries
_______ pressure is steady, pressure gradient is low, and its resistance is low.
Venous
Capillary exchange involves _______, ________, and _______.
Diffusion, transcytosis, and bulk flow
A decrease in BP at the arterial baroreceptors will result in an _________ in heart contractivity
Increase
Movement of fluids back into capillaries due to osmotic pressure, caused by plasma proteins.
Reabsorption
Movement of materials out due to BP.
Filtration
As fluid leaves due to filtration, BP _______.
Decreases
What 3 things can result in a change in BP?
Cardiac output, peripheral resistance, and blood volume.
As blood travels from arteries to veins, pressure ________.
Decreases
Blood flow to a tissue will increase if the:
arterioles dilate
Factors that promote the dilation of precapillary spincters
Vasodilators
The vasomotor center can control arterial BP by:
Making adjustments in vessel diameters.
Responds to changes in BP
Barorecptor reflexes
Monitor changes in the chemical composition of arterial blood.
Chemoreceptor reflexes
Barorecptors are found in:
Carotid sinuses, aortic sinuses, and the wall of the right atrium.
Responds to changes in CO, O, or pH levels in blood and cerebrospinal fluid.
Chemoreceptor reflexes
Chemoreceptor reflexes are located in:
Carotid and aortic arch
Released at the posterior lobe of the pituitary gland in response to a decrease in blood volume or an increase in the osmotic concentration of the plasma.
Antidiuretic Hormone (ADH)
