Chapter 19.1-19.7

List the five general classes of blood vessels.

-Arteries -Arterioles -Capillaries -Venules -Veins

Distinguish among the types of blood vessels on the basis of their structure and function.

-Arteries carry blood to the heart -Arterioles are the smallest arterial branches (arteries enter peripheral tissue, they branch repeatedly and the branches decrease in diameter) -Capillaries are where diffusion occurs between blood and interstitial fluid -Venules collect blood from capillaries -Veins unite with venules to become larger veins that return blood to heart.

Distinguish among efferent vessels ,afferent vessels and exchange vessels

-efferent vessels carry blood away the heart (arteries) -afferent vessels carry blood toward the heart (veins) -exchange vessels are capillaries because their thin walls allow exchange of nutrients, dissolved gases and wastes between blood and the surrounding interstitial fluid

Describe the pulmonary circuit

carries blood to and from the gas exchange surfaces to the lungs

Why are valves located in veins but not in arteries?

veins are more distensible/expandable then arteries and act as blood reservoirs to accommodate large volumes of blood

What factors are involved in the formation of varicose veins?

when blood backs up through the valves and pools in the veins and distends

Describe the distribution of total blood volume in the body.

64%- systemic venous system 9%- pulmonary circuit 7%- heart 13%- systemic arterial system 7%- systemic capillaries

Which is greater: arterial pressure or venous pressure?

Arterial pressure is much higher than venous pressure. It must push blood a greater distance through smaller vessels.

Identify the difference with afferent and efferent blood vessels

afferent vessels carry blood to the heart where efferent vessels carries blood away from it

At what sites in the body are fenestrated capillaries located

choroid plexus of the brain, capillaries of the hypothalamus, pituitary gland, pineal gland, and thyroid gland

Identify the two types of capillaries with a complete endothelium.

continuous capillary and fenestrated capillary

Neural and endocrine regulatory mechanisms influence which factors?

heart rate, stroke volume, peripheral resistance and venous pressure

Explain the effects of pressure, resistance, and venous return on cardiac output.

pressure- muscle compression and the respiratory pump are two factors that assist in propelling blood toward the heart at low venous pressure resistance- the force that opposes movement venous return- the amount of blood arriving in the right atrium each minute; direct impact on cardiac output

Which chamber of the body receives blood from the systemic circuit?

right atrium

Describe a capillary

the only blood vessels whose walls permit exchange between blood and interstitial fluid

Distinguish between the pulmonary and systemic circuits,

the pulmonary circuit carries blood to the lungs where the systemic circuit transports blood to and from the rest of the body

How is blood pressure maintained in veins to counter the force of gravity?

the veins have little valves the prevent blood from flowing backwards

Capillaries

thin walled vessels that interconnect the smallest arteries and veins

Describe the structures of capillaries and their functions in the exchange of dissolved materials between blood and interstitial fluid

thin walls that conduct diffusion but distance is short so exchange happens quickly

Why is it beneficial for capillary pressure to be very low?

to allow time for diffusion between the blood and surrounding interstitial fluid

Describe the systemic circuit

transports blood to and from the rest of the body