Unit 1 Lab 2

Question 1

what is the general path in systemic and pulmonary circulations

Answer 1

arteries > arterioles > capillaries > venues > veins

Question 2

what do capillaries do?

Answer 2

allow for the exchange of nutrients, wastes and gases between blood and body tissues

Question 3

what are the 3 layers of arteries?

Answer 3

• tunica interna
• tunica media
• tunica externa

Question 4

what makes up the tunica interna?

Answer 4

• endothelium
• basement membrane
• internal elastic lamina

Question 5

what makes up the tunica media?

Answer 5

smooth muscle and external elastic lamina

Question 6

what does endothelium in the tunica interna do?

Answer 6

• simple squamous epithelium

- forms a smooth slick lining to promote blood flow

Question 7

what does the basement membrane in the tunica interna do?

Answer 7

physical support base for endothelial layer = provides tensile strength and resilience for stretch and recoil

Question 8

what is the purpose of the internal elastic lamina?

Answer 8

it is elastic tissue

Question 9

what is the thickest layer in veins?

Answer 9

tunica externa

Question 10

what is the tunica external made of and what is its function?

Answer 10

elastic and collagen fibers and they provide support and protection

Question 11

is the vessel wall: vessel diameter ratio big or small in veins?

Answer 11

small

Question 12

describe the lumen in veins

Answer 12

larger than arteries and appears collapsed

Question 13

what do valves do?

Answer 13

prevent the back flow of blood

Question 14

what is in the blood reservoir?

Answer 14

majority of blood volume at rest is about 64% in venous circulation

Question 15

what do the venous valves make up?

Answer 15

the folds of the tunica interna

Question 16

what are the venous valves?

Answer 16

flap like cusps

Question 17

what are the 3 ways to overcome low pressure gradient and gravity to maintain venous return?

Answer 17

• skeletal muscle pump
• respiratory pump
• arterial pump

Question 18

what happens in the skeletal pump?

Answer 18

contraction of muscles surrounding veins to compress them

Question 19

what happens in the respiratory pump?

Answer 19

during inhalation diaphragm contracts and moves downwards increasing the pressure in abdominal cavity and decreasing the pressure in thoracic cavity
-> abdominal veins become compressed and blood moves to decompressed thoracic veins

Question 20

what happens in the arterial pump?

Answer 20

• constriction/dilation of arteries compress surrounding veins
• as an arterial pulse propagates along an artery, it pushes up against parallel veins

Question 21

what are capillaries?

Answer 21

extensive network of branched interconnected vessels

Question 22

what do capillaries do?

Answer 22

increase surface area available for rapid exchange of materials between blood and tissue cells

Question 23

what is endothelium made of in capillaries?

Answer 23

simple squamous epithelium

Question 24

what does endothelium of capillaries contain?

Answer 24

• tight junction
• intercellular clefts
• fenestrations
• and vesicles

Question 25

what are tight junctions?

Answer 25

fusion of plasma membranes of adjacent cells

Question 26

what are intercellular clefts?

Answer 26

spaces between cells

Question 27

what are fenestrations

Answer 27

pores in plasma membrane covered by a diaphragm

Question 28

how many blood cells can fit in a capillary?

Answer 28

smallest diameter so only one blood cell at a time

Question 29

what are the 3 types of capillaries?

Answer 29

- continuoud - fenestrated - sinusoidal

Question 30

what do continuous capillaries contain?

Answer 30

intercellular clefts

Question 31

what do fenestrated capillaries contain?

Answer 31

fenestrations

Question 32

what do sinusoidal capillaries contain?

Answer 32

- large fenestrations - large intercellular clefts - incomplete or absent basement membrane

Question 33

what is capillary exchange?

Answer 33

movement of substances between blood and interstitial fluid

Question 34

where does diffusion occur?

Answer 34

through intercellular clefts, fenestrations, or through lipid bilayer of endothelial cell plasma membranes

Question 35

what diffuses across membranes?

Answer 35

O2, CO2, glucose, amino acids, hormones

Question 36

what is transcytosis?

Answer 36

molecules transported across capillary walls by vesicles

Question 37

how does transcytosis happen?

Answer 37

substance in blood plasma packaged into vesicles -> vesicle travels across endothelial cell -> vesicle released into interstitial fluid

Question 38

what substances cross using transcytosis?

Answer 38

large lipid insoluble molecules, maternal antibodies passing into fetal circulation

Question 39

what instrument is used to measure arterial BP?

Answer 39

sphygmomanometer

Question 40

what artery do you used for BP?

Answer 40

brachial artery

Question 41

what are the sounds called when listening to BP?

Answer 41

korotkoff sounds

Question 42

what is a normal blood pressure?

Answer 42

120/80 mmHg

Question 43

what happens to BP during aerobic exercise?

Answer 43

- CO increases > stroke volume increases > arterial systolic BP increases - diastolic BP stays constant or decreases slightly = vasodilation

Question 44

what happens to BP during resistance exercise?

Answer 44

-arteries squeeze (vasoconstriction) > peripheral resistance increases > systolic and diastolic BP increases

Question 45

What is affected by vascular resistance?

Answer 45

- blood vessel lumen size - blood viscosity - total blood vessel length

Question 46

what is mitral valve prolapse?

Answer 46

one or both mitral valve cusps protrude into left atrium during ventricular contraction (sometimes leading to blood leaking back into left atrium)

Question 47

what are symptoms of MVP?

Answer 47

- dizziness - fatigue - chest pain - difficulty breathing

Question 48

what are risk factors of MVP?

Answer 48

- men of age 50+ | - linked to Marfan syndrome and muscular dystrophy

Question 49

how is a diagnosis for MVP made?

Answer 49

- auscultating for heart murmur with stethoscope | - echocardiogram

Question 50

what are treatments for MVP?

Answer 50

- surgery | - medications to manage symptoms

Question 51

what is a myocardial infarction?

Answer 51

complete obstruction to blood flow in a coronary artery > leads to death of cardiac tissue due to interrupted blood supply

Question 52

what are symptoms or MI?

Answer 52

- pressure, tightness, pain in chest and arms - nausea and indigestion - shortness of breath - cold sweat

Question 53

what are some risk factors for MI?

Answer 53

- men age 45+ and women age 55+ - high blood cholesterol - tobacco use - hypertension

Question 54

how is a diagnosis made for MI?

Answer 54

- ECG - blood test - coronary angiogram

Question 55

what are some treatments for MI?

Answer 55

- medications (blood thinners) | - surgery (coronary angioplasty)

Question 56

what are anastomoses?

Answer 56

alternative routes or detours for blood to flow

Question 57

definite trunk

Answer 57

short vessel that immediately branches

Question 58

define portal

Answer 58

vessel that connects two capillary beds