Chapter 14: The Cardiovascular System: Blood vessels, flow, and pressure

blood pressure

the pressure that is exerted by the blood against the walls of blood vessels

systolic pressure

Blood pressure in the arteries during contraction of the ventricles.

diastolic pressure

the pressure in the arteries when the heart is at rest

pulse pressure

the difference between systolic and diastolic blood pressure

Mean Arterial Pressure (MAP)

pressure forcing blood into tissues, averaged over cardiac cycle

resistance

The slowing or blocking of blood flow

flow rule

Flow = Pressure/Resistance

blood viscosity

the thickness and stickiness of blood

vasoconstriction

the constriction of blood vessels, which increases blood pressure.

cardiac output

The volume of blood ejected from the left side of the heart in one minute.

total peripheral resistance

the resistance of the entire cardiovascular system

systemic circuit

Circuit of blood that carries blood between the heart and the rest of the body.

pulmonary circuit

system of blood vessels that carries blood between the heart and the lungs

arteries

Blood vessels that carry blood away from the heart

arterioles

small vessels that receive blood from the arteries

capillaries

Microscopic vessel through which exchanges take place between the blood and cells of the body

venules

small vessels that gather blood from the capillaries into the veins

veins

Blood vessels that carry blood back to the heart

compliance

the ability of a vessel to respond to an increase in pressure by to distending or swell and increase the volume of blood it can hold, or with decreased pressure, a decrease in volume

pressure reservoir

the temporary storage of potential energy by elastic arteries as their walls are stretched by the incoming surge of blood, followed by the release of kinetic energy as the vessels recoil, which moves blood through the arteries

pores/fenestrations

holes in capillaries of glomerulus

simple diffusion

movement of a solute from an area of high concentration to an area of low concentration

transcytosis

moving substances into, across, and then out of a cell

carrier mediated transport

The type of transport in which proteins bind to ions or substrates and carry them across the plasma membrane

precapillary sphincters

control the blood flow into capillary beds.

lymphatic system

the network of vessels through which lymph drains from the tissues into the blood.

osmotic pressure

the external pressure that must be applied to stop osmosis

capillary hydrostatic pressure

facilitates the outward movement of water from the capillary to the interstitial space

interstitial fluid hydrostatic pressure

the pressure created by fluid located in the interstitial spaces which helps push fluid and solutes into capillaries

capillary osmotic pressure

pulls water into the capillary; albumin is the major contributor

interstitial fluid osmotic pressure

inward pulling force of particles in the interstitial fluid

edema

puffy swelling of tissue from the accumulation of fluid

volume reservoirs

Veins serve as blood reservoirs because they are able to stretch and hold onto a larger percentage of blood volume

venous pressure

pressure in the venous system

venous return

The amount of blood returned to the heart by the veins

end-diastolic volume

volume of blood in each ventricle at end of ventricular diastole

stroke volume

The amount of blood ejected from the heart in one contraction.

skeletal muscle pump

pumping effect of contracting skeletal muscles on blood flow through underlying vessels

respiratory pump

Is composed of skeletal structures (bones) and soft tissues (muscles) that work together to allow proper respiratory mechanics to occur and help pump blood back to the heart during inspiration.

venomotor tone

The degree of muscle tone present within venous walls to promote venous return

atherosclerosis

hardening of the arteries

hypotension

abnormally low blood pressure

hypertension

abnormally high blood pressure

autoregulation

the ability of tissues to regulate their own blood supply

active hyperemia

increased blood flow in response to increased metabolic activity

reactive hyperemia

redness of the skin resulting from dilation of the superficial capillaries

myogenic response

change in vascular resistance in response to stretch of blood vessels in the absence of external factors

vasoactive chemicals

substances that stimulate vasomotion; histamine, bradykinin

nitric oxide

a gas released by the endothelial cells to promote blood flow

histamine

A chemical that is responsible for the symptoms of an allergy

prostacyclin

inhibits blood clotting and vasoconstriction

cardiovascular control center

the area of the medulla that regulates the cardiovascular system

medulla oblongata

Part of the brainstem that controls vital life-sustaining functions such as heartbeat, breathing, blood pressure, and digestion.

baroreceptors

Cells that are sensitive to blood pressure changes.

chemoreceptors

chemical sensors in the brain and blood vessels that identify changing levels of oxygen and carbon dioxide

adrenal medulla

secretes epinephrine and norepinephrine

ADH

antidiuretic hormone (vasopressin)

aldosterone

Hormone that stimulates the kidney to retain sodium ions and water

hypothalamus

brain structure that acts as a control center for recognition and analysis of hunger, thirst, fatigue, anger, and body temperature