Circulatory System

Question 1

Functions of the Circulatory System (4)

Answer 1

1) Carries blood from heart to body & back
2) Allows nutrient, waste & gas exchange with tissues.
3) Transport other substances (hormones, enzymes, etc.) through body
4) Regulates blood pressure & blood flow to the tissues

Question 2

Circulatory System consists of what 2 systems

Answer 2

Cardiovascular & Lymphatic systems

Question 3

How does blood flow from the heart?

Answer 3

Through elastic arteries, muscular arteries, arterioles, to capillaries.

Question 4

Cardiovascular systems consists of….

Answer 4

Blood Vessels & the Heart

Question 5

How does blood flow to the heart?

Answer 5

From capillaries through venules, small veins, & large veins.

Question 6

What are the 3 layers of a blood vessel?

Answer 6

1) Tunica externa
2) Tunica media
3) Tunica interna

Question 7

Tunica Interna (3)

Answer 7

1) Innermost layer of blood vessels
2) Direct contact with LUMEN
3) Consists of Endothelium (simple squamous ET) & a layer of elastic CT (connective tissue)

Question 8

Tunica Media (3)

Answer 8

1) Middle layer of blood vessels
2) Thick
3) Consists of smooth muscle & elastic fibers

Question 9

Tunica Externa (3)

Answer 9

1) Outermost layer of blood vessel
2) Extremely strong & elastic
3) Contains large amounts of Protein fibers

Question 10

What are the 3 types of Arteries?

Answer 10

1) Large elastic arteries
2) Muscular Arteries
3) Arterioles

Question 11

Function of Arteries (3)

Answer 11

1) Carry blood from heart to body (directly to arterioles)
2) LOW-RESISTANCE CONDUITS- they ease blood flow and allow for constant pressure
3) PRESSURE RESERVOIRS- Stretching and recoiling help maintain pressure created,during systole (heart contraction)

Question 12

Aneurysm

Answer 12

Blow out blister within an artery

Question 13

Vasoconstriction

Answer 13

-Contractility (constriction of blood vessels by small smalls in their walls)

Question 14

Vasodilation

Answer 14

• Elasticity (dilation of blood vessels to allow more blood flow and lower blood pressure)

Question 15

Large Elastic (conducting) Arteries (4)

Answer 15

1) Thin-walled & large in diameter
2) It’s Tunica Media layer has MANY elastic fibers & FEW smooth muscle
3) Ones closest to heart
4) FUNCTIONS AS A PRESSURE BUFFER (expands during systole)

Question 16

Muscular (distributing) Arteries (4)

Answer 16

1) Thick-walled & small in diameter
2) It’s Tunica Media layer has MANY smooth muscle & FEW elastic fibers
3) Adjust blood volume via vasoconstriction & dilation
4) EX: Intercostal, Brachial, Radial, & Axillary

Question 17

Arterioles (2)

Answer 17

1) Small narrow branches of arteries
2) It’s Tunica Media has smooth muscle fibers & FEW elastic fibers

Question 18

Endothelium

Answer 18

Simple squamous epithelium that lines the entire circulatory sysem

Question 19

Capillaries (properties- 7)

Answer 19

1) Most common type of blood vessel 2) Thinnest walls
3) Consist only of endothelium
4) Surrounded by Externa (loose connective tissue) that contains Pericapillary cells
5) Do not exist individually but form branching networks
6) Low BP inside
7) Allows transport/exchange of materials with blood

Question 20

3 Types of Capillaries

Answer 20

1) Continuous Capillaries
2) Fenestrated Capillaries
3) Sinusoidal Capillaries

Question 21

Continuous Capillaries (2)

Answer 21

1) Have no gaps between the endothelial cells (less permeable to large molecules)
2) located in muscle & nervous tissue

Question 22

Fenestrated Capillaries (2)

Answer 22

1) Have pores called Fenestrae that extend completely though the cell (highly permeable)
2) Located in intestinal villie, ciliary processes of eye, & choroid plexus of CNS

Question 23

Sinusoidal Capillaries (2)

Answer 23

1) large-diameter capillaries with large fenestrate
2) located liver & endocrine glands

Question 24

How do materials pass through capillaries? (3)

Answer 24

1) between endothelial cells
2) through fenestrae
3) through plasma membrane

Question 25

How does blood travel though capillary networks? (2)

Answer 25

1) Arterioles supply blood through metarterioles --> thoroughfare channel --> venule 2) Blood flow is regulated by precapillary sphincters

Question 26

Arteriovenous Anastomoses

Answer 26

Specialized vascular connections that allow blood to flow directly from arterioles to small veins without passing through capillaries

Question 27

Veins vs. Arteries (4)

Answer 27

1) Veins carry deoxygenated blood to the heart, arteries carry oxygenated blood away 2) Veins are thinner 3) Vein walls contain less elastic tissue & smooth muscle fibers 4) Veins closer to the heart have thicker walls and are greater in diameter

Question 28

Veins- Structure (3)

Answer 28

1) Smaller than arteries 2) Thinner, weaker, less elastic walls 3) Contain valves that prevent blood backflow

Question 29

Veins- Function & Important Property (2)

Answer 29

1) Carry blood from venules toward the heart 2) BP is low within veins

Question 30

Valves (3)

Answer 30

1) Prevents blood backflow 2) In veins that are larger than 2mm in diameter (many medium veins) 3) More valves in lower limb veins than upper limb -

Question 31

Venules (3)

Answer 31

1) Narrow vessels similar to veins 2) Carry blood from capillaries to veins 3) Walls consist of 3 tunics when to close to veins BUT no tunica media when close to capillaries

Question 32

Pulmonary Circulation

Answer 32

Circulation of blood between HEART & LUNGS

Question 33

Pulmonary Arteries vs. Pulmonary Veins (2)

Answer 33

1) Arteries carry deoxygenated blood from the heart to the lungs 2) Veins carry oxygenated blood from the lungs to the heart

Question 34

Systemic Circulation

Answer 34

Circulation of blood between the HEART & BODY TISSUES

Question 35

Veins of Systemic Circulatory System (7)

Answer 35

1) Superior Vena Cava 2) Inferior Vena Cava 3) Common Iliac Vein 4) Femoral Vein 5) Internal Jugular Vein 6) Renal Vein 7) Subclavian Vein

Question 36

Arteries of Systemic Circulatory System (8)

Answer 36

1) Aorta 2) Brachial Artery 3) Common Carotid Artery 4) Common Iliac Artery 5) Femoral Artery 6) Radial Artery 7) Renal Artery 8) Subclavian Artery

Question 37

How many pulmonary veins empty blood into the left atrium?

Answer 37

4