Week 5: Blood Vessels

Question 1

What are the 3 layers of a blood vessel?

Answer 1

Tunica Interna
Tunica Media
Tunica Externa

Question 2

Define an artery

Answer 2

Carries blood away from the heart to other organs

Question 3

What does vasoconstriction mean?

Answer 3

A decrease in the diameter of the lumen of a blood vessel

Question 4

What does vasodilation mean?

Answer 4

The increase in the lumen of the diameter

Question 5

What is the function of the elastic arteries?

Answer 5

They help propel blood onward while the ventricles are relaxing. They include the aorta and pulmonary trunk. They are the biggest arteries.

Question 6

What is the function of muscular arteries?

Answer 6

Medium sized. They distribute blood to each of the various organs. Eg: Brachial artery & radial artery.

Question 7

What is the function of of arterioles?

Answer 7

The smallest.

They regulate the flow of blood into the capillary networks of the body’s tissues.

Question 8

What is the relationship between anastamoses and collateral circulation?

Answer 8

Anastomoses is an alternative route of blood flow. The alternative route is know as collateral circulation.

Question 9

What is the structure and function of capillaries?

Answer 9

Function: The change of substances between the blood and interstitial fluid.

Structure: Have a single layer of endothelial cells and a basement membrane.

Question 10

Define auto regulation of capillary flow.

Answer 10

Adjusts blood flow through a capillary bed in response to physical and chemical changes in a tissue

Question 11

What are 3 different types of capillaries?

Answer 11

Continuous - limited diffusion

Fenestrated - quick fluid, larger exchange

Sinusoids - large, incomplete basement membrane, quite leaky

Question 12

What is capillary blood pressure?

Answer 12

Pushes fluids out of capillaries into interstitial fluid

Question 13

What is colloid osmotic pressure?

Answer 13

Pulls fluid into the capillaries from interstitial fluid

Question 14

Define venules

Answer 14

Are small vessels that collect blood from capillaries and drain into veins

Question 15

Define veins

Answer 15

Have thinner tunica Interna and tunica media than arteries.

Question 16

Why are valves necessary in veins?

Answer 16

To prevent back flow of blood.

Question 17

What are 3 factors that assist in venous return?

Answer 17

Pumping action of the heart

Skeletal muscle contractions

Pressure changes associated with breathing

Question 18

What are all the arteries?

Answer 18

Elastic 
Muscular 
Arterioles 
Capillaries 
Venules 
Veins

Question 19

What is the main function of capillaries?

Answer 19

Permit exchange of nutrients and wastes between flood and interstitial fluid.

Question 20

What are 3 factors that assist in venous return?

Answer 20

Pumping action of the heart

Skeletal muscle contractions

Pressure changes associated with breathing

Question 21

What are all the arteries?

Answer 21

Elastic 
Muscular 
Arterioles 
Capillaries 
Venules 
Veins

Question 22

What is the main function of capillaries?

Answer 22

Permit exchange of nutrients and wastes between flood and interstitial fluid.

Question 23

What are 3 factors that assist in venous return?

Answer 23

Pumping action of the heart

Skeletal muscle contractions

Pressure changes associated with breathing

Question 24

What are all the arteries?

Answer 24

Elastic 
Muscular 
Arterioles 
Capillaries 
Venules 
Veins

Question 25

What is the main function of capillaries?

Answer 25

Permit exchange of nutrients and wastes between flood and interstitial fluid.

Question 26

Define blood flow

Answer 26

The volume of blood flowing through a tissue in a given period.

Question 27

Define blood pressure

Answer 27

The pressure exerted by blood on blood vessel walls. 120/80 or 60

Question 28

What is cardiac output?

Answer 28

Total blood flow + volume of blood flowing through all systematic blood vessels each minute

Question 29

Where is the cardiovascular centre found?

Answer 29

Medulla Oblongata

Question 30

What are the sensory receptors that provide input into the cardiovascular system?

Answer 30

Baroreceptors and Chemoreceptors

Question 31

What do baroreceptors do?

Answer 31

Pressure-sensitive sensors that monitor blood pressure

Question 32

What do chemoreceptors do?

Answer 32

Monitor blood levels of oxygen, carbon dioxide and hydrogen ions

Question 33

How do hormones regulate blood pressure?

Answer 33

Angiotensin II & Antidiuretic Hormone cause vasoconstriction Aldosterone increases blood volume. Epinephrine and norepinephrine increase cardiac output and cause vasoconstriction. Atrial natriuretic peptide causes vasodilation.

Question 34

Tachycardia

Answer 34

Rapid heart rate over 100 beats

Question 35

Bradycardia

Answer 35

A slow resting heart or pulse rate under 50bpm

Question 36

Pulmonary circulation

Answer 36

Carries deoxygenated blood from the right ventricle to the air sacs of the lungs and returns oxygenated blood from the air sacs to the left atrium

Question 37

The systemic circulation

Answer 37

Carries oxygenated blood from the left ventricle to systemic capillaries throughout the body and returns the deoxygenated blood to the right atrium.

Question 38

What are the 4 regions of the aorta?

Answer 38

Ascending aorta Arch aorta Thoracic aorta Abdominal aorta

Question 39

What regions are drained by the superior vena cava?

Answer 39

Blood from veins above the diaphragm

Question 40

What regions are drained by the inferior vena cava?

Answer 40

Veins below the diaphragm and the coronary sinus drains the heart wall.