Ch. 22 (blood vessels) Study guide

Question 1

fetal circulation

Answer 1

all fetal nutritional and respiratory needs are provided by diffusion across the placenta; blood is delivered to the placenta thru umbilical arteries; oxygenated blood is delivered out by the umbilical vein into the ductus venosus; then it enters the heart at the inferior vena cava; blood then goes thru the heart to the lungs and ductus arteriosus and also the internal iliac arters (which give blood to the umbilical arteries)

Question 2

Arteries

Answer 2

“supply”; carry oxygenated blood from heart to peripheral capillaries; 3 types = elastic, muscular, and arterioles

Question 3

Veins

Answer 3

“drain”; carry deoxygenated blood towards the heart for purification; much smaller/thinner

Question 4

Portal system

Answer 4

Network of blood vessels connecting to two capillary beds (2 main ones = hepatic and hypophyseal)

Question 5

Hepatic portal system

Answer 5

Blood leaves the capillary beds supplied by 3 arteries which flows into veins of this portal system (the liver is drained by the inf. vena cava)

Question 6

3 types of capillaries

Answer 6

Continuous, sinusoids, and fenestrated

Question 7

Capillaries

Answer 7

smallest and most delicate blood vessels; important because they are the only blood vessels whose walls permit exchange between the blood and the surrounding interstitial fluid

Question 8

Continuous capillaries

Answer 8

found most everywhere; endothelium is a complete lining and those cells are connected by tight junctions

Question 9

Fenestrated capillaries

Answer 9

Capillaries that contain windows or pores in their walls; due to incomplete lining; found in choroid plexus of brain

Question 10

Sinusoid capillaries

Answer 10

largest pores and thinner basal lamina; found in liver and bone marrow

Question 11

Blood flow in capillaries

Answer 11

controlled by capillary autoregulation; blood reaches venules by 1 route now and a different route later

Question 12

Systemic circulation

Answer 12

It supplies all capillary beds not already supplied by pulmonary circuit; contains on average about 84 % of blood volume; takes blood away from heart in arteries and brings deoxygenated blood back

Question 13

Pulmonary circulation

Answer 13

Oxygen is replenished, CO2 is excrte, and oxygenated blood returns to heart for distribution to the body; brings deoxygenated blood away from the heart in veins to the lungs to get reoxygenated and brings oxygenated blood back; much lower pressure than the other circulation

Question 14

Vessels carrying most blood at rest?

Answer 14

systemic venous system (liver, bone marrow skin), venules and medium sized veins