Chapter 21: The Blood Vessels

Front 1

ARTERIES

Back 1

carry blood away from heart to other organs.

Front 2

ARTERIOLES

Back 2

arteries divide into smaller arteries

Front 3

CAPILLARIES

Back 3

arterioles enter tissue, branch into numerous tiny vessels

Front 4

VENULES

Back 4

Groups of capillaries within tissue reunite to form small veins

Front 5

VEINS

Back 5

venules merge to form progressively larger blood vessels. convey blood from tissues back to the heart.

Front 6

CAPILLARY EXCHANGE

Back 6

A

Front 7

DIFFUSION

Back 7

A

Front 8

TRANSCYTOSIS

Back 8

A

Front 9

BULK FLOW

Back 9

A

Front 10

FILTRATION

Back 10

A

Front 11

REABSORPTION

Back 11

A

Front 12

BLOOD HYDROSTATIC PRESSURE (BHP)

Back 12

A

Front 13

INTERSTITIAL FLUID OSMOTIC PRESSURE (IFOP)

Back 13

A

Front 14

BLOOD COLLOID OSMOTIC PRESSURE (BCOP)

Back 14

A

Front 15

NET FILTRATION PRESSURE (NFP)

Back 15

A

Front 16

EDEMA

Back 16

A

Front 17

BLOOD FLOW

Back 17

A

Front 18

BLOOD PRESSURE

Back 18

A

Front 19

SYSTOLIC BLOOD PRESSURE

Back 19

A

Front 20

DIASTOLIC BLOOD PRESSURE

Back 20

A

Front 21

MEAN ARTERIAL BLOOD PRESSURE (MAP)

Back 21

A

Front 22

VASCULAR RESISTANCE

Back 22

S

Front 23

BLOOD VISCOSITY

Back 23

A

Front 24

TOTAL BLOOD VESSEL LENGTH

Back 24

A

Front 25

SYSTEMATIC VENOUS RETURN (SVR) / TOTAL PERIPHERAL RESISTANCE (TPR)

Back 25

A

Front 26

VENOUS RETURN

Back 26

A

Front 27

SKELETAL MUSCLE PUMP

Back 27

A

Front 28

RESPIRATORY PUMP

Back 28

S

Front 29

VELOCITY OF BLOOD FLOW

Back 29

L

Front 30

CIRCULATION TIME

Back 30

A

Front 31

TYPES OF BLOOD VESSELS

Back 31

arteries, arterioles, capillaries, venules, veins

Front 32

TUNICA INTERNA

Back 32

forms inner lining of blood vessel and in direct contact with blood as it flows through lumen

Innermost layer endothelium, continuous with endocardial lining of the heart; thin layer of flattened cells.

Basement membrane, anchors endothelium to underlying connective tissue while also regulating molecular movement.

Internal elastic lamina forms boundary between tunica interna and tunica media, facilitate diffusion of materials

Front 33

LUMEN

Back 33

interior opening of vessel.

Front 34

TUNICA MEDIA

Back 34

thick layer compromised of smooth muscle cells and elastic fibers.

Regulates diameter of lumen

Front 35

VASOCONSTRICTION

Back 35

increase in sympathetic stimulation causes smooth muscle to contract, narrowing lumen; decrease in diameter of lumen

Front 36

VASODILATION

Back 36

Sympathetic stimulation decreases, smooth muscle relaxes, increase in lumen diameter

Front 37

TUNICA EXTERNA

Back 37

consists of elastic and collagen fibers, numerous nerves

Front 38

VASA VASORUM

Back 38

tiny blood vessels supply tissue of vessel wall, found in larger vessels of tunica externa.

Front 39

ELASTIC (CONDUCTING) ARTERIES

Back 39

largest arteries in body, large diameter but thin walls

well-defined internal & external elastic laminae, thick tunica media dominated by elastic fibers, called elastic lamellae.

help propel blood onward while ventricles relaxing

Front 40

MUSCULAR ARTERIES

Back 40

tunica media contains more smooth muscle and fewer elastic fibers.

Continue to branch and distribute blood to each organ, distributing arteries.

Maintains vascular tone, maintains vessel pressure and efficient blood flow.

Front 41

ANASTOMOSIS

Back 41

union 2+ artery branches supplying same body region.

Front 42

ARTERIOLES

Back 42

Regulate flow of blood into capillary networks of body’s tissues.

Thin tunica interna with thin fenestrated internal elastic lamina

Front 43

METARTERIOLES

Back 43

Terminal end of arteriole, tapers toward capillary junction.

Front 44

PRESSURE SPHINCTER

Back 44

At metarteriole capillary junction muscle cells form ---- monitors blood flow into capillary.

Front 45

RESISTANCE

Back 45

the opposition to blood flow.

Contraction of smooth muscle of arteriole causes vasoconstriction, increases ----- and decreases blood flow into capillaries.

Relaxation of smooth muscle of arteriole causes vasodilation, decreases ----- and increases blood flow into capillaries.

Front 46

CAPILLARIES

Back 46

Smallest blood vessels, forms U turn that connect arterial outflor to venous return.

Primary function is exchange of substances between blood and interstitial fluid.

Body tissues with high metabolic requirements (brain, liver, kidneys) have extensive capillary networks.

Composed of only single layer of endothelial cells and basement membrane.

Front 47

MICROCIRCULATION

Back 47

flow of blood from met arteriole through capillaries into post capillary venule.

Front 48

CAPILLARY BED

Back 48

network of 10-100 capillaries that arise from single metarteriole.

Front 49

THOROUGHFARE CHANNEL

Back 49

distal end of vessel with no smooth muscle

Provides direct route for blood from arteriole to a venule, bypassing capillaries.

Front 50

CONTINUOUS CAPILLARIES

Back 50

plasma membranes of endothelial cells form continuous tube that is interrupted by intercellular clefts, gaps between neighbouring cells.

CNS, lungs, skin, muscle tissue

Front 51

FENESTRATED CAPILLARIES

Back 51

plasma membranes have many fenestrations, small pores.

Kidneys, choroid plexuses of brain, endocrine glands

Front 52

SINUSOIDS

Back 52

unusually large fenestrations, large intercellular clefts that allow proteins, blood cells to pass from tissue into bloodstream.

Liver, spleen, anterior pituitary, adrenal glands.

Front 53

PORTAL SYSTEM

Back 53

some parts of body blood passes from one capillary network into another through portal vein

Front 54

VENULES

Back 54

Thin walls do not readily maintain their shape. Drain capillary blood and begin to return flow of blood back toward heart.

Front 55

VEINS

Back 55

Composed of same 3 layers as arteries, relative thickness differs; tunica interna & media of veins is much thinner, tunica externa thickest layer and consists of collagen & elastic fibers.

Average BP considerably lower than arteries; blood leaves cut vein slowly, but will spurt rapidly from cut artery

Front 56

VALVES

Back 56

thin folds of tunica interna that form flaplike cusps in veins. Cusps project into lumen, pointing toward heart.

Front 57

VASCULAR (VENOUS) SINUS

Back 57

vein with thin endothelial wall with no smooth muscle to alter its diameter.

Front 58

SUPERFICIAL VEINS

Back 58

course through subcutaneous layer unaccompanied by parallel arteries. Form small connections (anastomoses) with deep veins that travel between skeletal muscles.

Front 59

BLOOD DISTRIBUTION

Back 59

largest portion of blood vol at rest (64%) in systematic veins & venules.

Front 60

BLOOD RESERVOIRS

Back 60

systematic veins and venules, blood can be diverted quickly if necessary.