Blood Vessels pt. 1

Question 1

What are the 2 main artery systems?

Answer 1

Pulmonary + Systemic

Question 2

What are the 3 layers of the vessel wall and what are they made of?

Answer 2

Tunica Intima - elastic fiber
Tunica Media - collagen fiber
Tunica Externa - collagen + elastic fibers

Question 3

What is Lumen and is there more lumen in arteries or veins?

Answer 3

Lumen is the space inside the vessel and there’s more lumen in veins because of more elastic recoil

Question 4

What is vasoconstriction/vasodilation?

Answer 4

When smooth muscles contract and dilate

Question 5

What are the 3 main arteries and what do they do?

Answer 5

Elastic (conducting) carries blood out of the heart
Muscular (distributive) distributes to the body
Arterioles (resistance) maintain resistance/blood pressure

Question 6

What is an aneurysm?

Answer 6

A bulge in the wall of an artery

Question 7

What are the 2 types of capillaries and what characteristics do they have?

Answer 7

Continuous and Fenestrated.
Continuous - supplies most parts of body, prevents blood loss
Fenestrated - have pores/”windows” to allow quick exchange of nutrients

Question 8

What is vasa vasorum?

Answer 8

Small blood vessels that supply the walls of arteries and veins

Question 9

What are Precapillary sphincters?

Answer 9

They guard the entrance of capillaries

Question 10

What are the precapillary arterioles and thoroughfare channels used for?

Answer 10

Precapillary arterioles regulate blood flow into capillaries, and thoroughfare channels provide a direct route for blood flow to bypass capillaries when necessary.

Question 11

What is angiogenesis and why is it important?

Answer 11

When new blood vessels are formed from pre-existing vessels and this helps repair or replace damaged blood vessels

Question 12

What is vasomotion?

Answer 12

changes in vessel diameter

Question 13

What are the functions of venous valves?

Answer 13

One-way flow prevents backflow
Improves venous return
Compartmentalize blood to contract and push it toward the heart

Question 14

What happens when you hemorrhage

Answer 14

Systemic veins constrict - vasoconstriction keeps more blood in arteries and capillaries

Constriction of the lungs, skin, and liver redistributes blood to more important organs like the brain

Question 15

What are the three kinds of pressure in your body?

Answer 15

Blood pressure (BP) - arterial pressure
Capillary Hydrostatic Pressure (CHP) - pressure within capillaries
Venous pressure - pressure in venous system

Question 16

What 3 factors does total peripheral resistance consist of?

Answer 16

Vascular resistance, Blood viscosity, and Turbulence

Question 17

What is vascular resistance and if the diameter of a vessel gets smaller, does friction increase or decrease?

Answer 17

Increasing vessel length and decreasing vessel diameter increases resistance (friction), less diameter = more friction

Question 18

What is turbulence (total peripheral resistance) and how does it affect resistance?

Answer 18

Turbulence consists of high flow rates, irregular surfaces, and sudden changes in vessel diameter so blood wont flow as smoothly, causing more resistance

Question 19

What factors affect cardiovascular pressure?

Answer 19

Vessel Diameter
Total cross-sectional area
Pressures
Velocity of blood flow

Question 20

What’s the difference between hypotension and hypertension?

Answer 20

Hypertension - high blood pressure
Hypotension - low blood pressure

Question 21

When blood travels against gravity, what 2 factors help push it to the heart?

Answer 21

muscular compression of peripheral veins - contractions from skeletal muscles

respiratory pump during inhalation - pressure rises to force air out of the lungs

Question 22

How do capillaries contribute to homeostasis?

Answer 22

Diffusion, Filtration, Absorption

Question 23

What is diffusion and when does it occur?

Answer 23

Diffusion: movement of ions from higher to lower concentration
Occurs when - distances are shorter, concentration is large, ions/molecules smaller

Question 24

What is filtration and where does it occur?

Answer 24

Filtration: removing solutes from a solution
Takes place at the arterial end of a capillary

Question 25

Define osmosis

Answer 25

higher concentration of water to lower concentration

Question 26

What is osmotic pressure and why is it important to the body?

Answer 26

Osmotic pressure - the pressure required to keep a solute from diffusing from solution

Helps extract nutrients from food

Question 27

Why is moving water through the capillaries important?

Answer 27

• It accelerates the distribution of nutrients, hormones, and dissolved gasses throughout tissues
• Assists the transport of lipids and tissue proteins that cant enter the bloodstream by crossing the capillary walls
• A flushing action carrying toxins and other chemicals to tissues and organs responsible for providing immunity to disease.

Question 28

What is tissue perfusion?

Answer 28

mechanisms that make sure blood flows through tissues.