Ch 21 Blood vessels and circulation

Question 1

Functions of circulatory system

Answer 1

carry blood
exchange nutrients, waste products, gases
transport 
regulate blood pressure
direct blood flow

Question 2

Arteries

Answer 2

thicker muscle walls than veins, more elastic tissue and smooth muscle tissue

Question 3

Capillaries

Answer 3

sites of exchange within tissue

Question 4

Veins

Answer 4

thinner walls than arteries, less elastic tissue and fewer smooth muscle cells

Question 5

Vasa vasorum

Answer 5

blood vessels that supply walls of arteries and veins.

Question 6

Artery tunica externa (adventitia)

Answer 6

Outer layer
consists of connective tissue
dense regular near vessel and loose ct merges with surrounding ct

Question 7

Artery tunica media

Answer 7

Middle layer

smooth muscle- allows for vasoconstriction and vasodilation

Question 8

Artery tunica intima

Answer 8

innermost layer
thin layer of connective tissue called lamina propria (basement membrane) and internal elastic lamina which contains elastic fibers

Question 9

Anatomy of veins

Answer 9

3 layers, but tunica media is thinner than in arteries (less smooth muscle)
have one way valves that allow blood flow to the heart only (one-way blood flow)

Question 10

Elastic/conducting arteries

Answer 10

Large arteries
pressure is highest and fluctuates between systolic and diastolic
most elastic tissue than muscular tissue
relatively thick tunica media and thin tunica intima

Question 11

Muscular arteries - medium

Answer 11

smooth muscle allows vessels to regulat blood suppy by constricting or dilating
most of smaller, unnamed arteries
thick walls (25-40 layers of smooth muscle)
distributing arteries- smooth muscle allows them to partially regulate blood supply to diff regions of the body

Question 12

Small muscular arteries

Answer 12

adapted for vasodilation and constriction

Question 13

arterioles

Answer 13

transport blood from small arteries to capillaries

capable of vasodilation and constriction

Question 14

Capillaries anatomy

Answer 14

layer of simple squamous epithelium and basal lamina

cells called pericytes wrap around to help regulate blood flow and establish bbb

Question 15

Substances move through capillaries by…

Answer 15

diffusion

Question 16

Larger water soluble molecules move through… in capillaries

Answer 16

fenestrae

Question 17

Continuous capillaries

Answer 17

found in tissue
least permeable
most abundant
allow for small substances to pass through

Question 18

Fenestrate capillaries

Answer 18

Found in glomeruli of kidneys

have larger gaps called fenestrations for passage of more substances

Question 19

Sinusoid capillaries

Answer 19

found in adrenal gland, liver, bone marrow, spleen
most permeable
incomplete basement membrane and intercellular gap allow for more substances to flow through

Question 20

Capillary network bloodflow pathway (closed sphincters)

Answer 20

artieriole–>metarteriole–>thoroughare channel–>venule

Question 21

Capillary network bloodflow pathway (open sphincters)

Answer 21

ateriole–>matarteriole–>capillaris–>thoroughfare channel–>venule

Question 22

Venules

Answer 22

drain capillar network; made of endothelial cells and basement membrane with few smooth muscle cells

Question 23

Small veins

Answer 23

smooth muscle cells form continuous layer; addition of tunica adventitia made of collagenous connective tissue

Question 24

Medium veins

Answer 24

go between small and large veins

Question 25

Large veins

Answer 25

thin tunica intima
endothelial cells form relatively thin layer of CT
Tunica media has cicularly arranged smooth muscle cells
prominent layer is the adventitia

Question 26

Valves in veins

Answer 26

exist in veins that are 2mm in diameter or greater
folds in intima form 2 flaps that overlap
more valves in lower extremity than upper
in combo with skeletal muscle pump, valves help return blood flow to the heart

Question 27

Systole

Answer 27

Heart is squeezing

Question 28

Diastole

Answer 28

Heart is relaxing; refilling

Question 29

Blood flow to upper limb

Answer 29

sublavion a–>axillary a–>brachial and humeral circumflex a. –> radial/ulnar a–> superficial/deep a palmar arches

Question 30

Blood flow to abdomen

Answer 30

Descending aorta–> celiac a–> renal a–> superior/inferior mesenteric a –> common iliac a–> internal/external iliac a

Question 31

Blood flow to lower limb

Answer 31

External iliac a–> femoral a and circumflex a–> anterior tibial a–> popliteal a–> posterior tibial a and fibular a –> superficial and deep plantar arches

Question 32

Blood flow from brain

Answer 32

superficial and inferior saggital sinus–> straight sinus–> transverse sinus–> internal jugular vein

Question 33

Blood flow from upper limb

Answer 33

superficial/deep venous arches–> radial v–> ulnar v–> median antebrachial v–> basilic v–> cephalic v–> medial cubital v–> brachial v–> axillary v–> subclavion v–> brachiocephalic v–> superior vena cava

Question 34

Blood flow from abdomen

Answer 34

superior mesenteric and inferior mesenteric and splenic veins–> hepatic portal–> through liver–> inferior vena cava

Question 35

Blood flow from lower limb

Answer 35

Venous arches–> great and small saphenous and anterior tibial vein–> femoral v–> external iliac v–> common iliac v–> inferior vena cava