EXAM 3: SEC 1/blood Flashcards Preview

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Flashcards in EXAM 3: SEC 1/blood Deck (58):
1

Blood

- made of formed elements (cells, cell fragments, plasma)
- plasma carries blood cells, proteins, nutrients, metabolic wastes, and other molecules being transported around the body

2

Cardiovascular System Overview

- 2 loops: systemic and pulmonary
- closed system

3

Systemic Loop

- carries blood from heart to the rest of the body

4

Pulmonary Loop

- carries oxygen-poor blood to lungs and back to heart

5

Parasympathetic Innervation

- releases acetylcholine through vagus nerve into atria

6

Sympathetic Innervation

- releases norepi & epi through thoracic spinal nerves and bloodstream into atria and ventricles

7

P wave

- atrial depolarization

8

QRS complex

- atrial repolarization
- ventricular depolarization

9

T wave

ventricular repolarization

10

Normal open valve heart sound

- quiet and laminar flow

11

Stenotic valve sound

- turbulent flow
- murmur

12

Normal closed valve sound

- quiet, no flow

13

Insufficient valve sound

- leaky valve
- turbulent backflow
- murmur

14

Positive chronotropic factors

things that increase heart rate

15

Negative chronotropic factors

things that decrease the heart rate

16

Regulation of HR

- HR is controlled by the input from the nervous system: SNS increases HR, PSNS decreases HR
- AP created sooner via sympathetic stimulation increases HR creating more positive mem
- AP created later via parasympathetic decreases HR creating negative mem

17

Frank-Starling Mechanism

- increase ventricular filling/preloading = increase in stroke volume = increase in cardiac output
- decrease preload = decrease stroke volume = decrease cardiac output
- norepi from sympathetic increases intracell calcium concentration increasing contractile force, increasing contractility, faster and stronger contractions and increasing HR with greater force development

18

2 ways cardiac contractile force is regulated

- starling's law (the effect of preload) and contractility (the effect of external neural, hormonal stimulation)

19

Vascular System

- pressure in system falls as passes from one end to other
- pressure in pulmonary circulation is lower than in systemic

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upstream pressure systemic

aorta

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downstream pressure systemic

right atrium

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pulmonary circulation upstream

pulmonary artery

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pulmonary circulation downstream

left atria

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lowest pressure in heart

right atrium

25

Arteries

- compliance = change in vol / change in pressure
- the higher the compliance, the more easily can be stretched
- arteries are often called pressure reservoirs because of the elastic recoil - not as compliant as veins
- arteries stretch during systole and relax/squeeze down on blood during diastole

26

diastole pressure

- lowest pressure

27

arterial pressure changes due to

age, stiffness, systolic pressure

28

Active Hypermia

increase metabolic activity of organ
to
decrease O2, increase metabolites in organ interstitial fluid
to
arteriolar dilation in organ
to
increase blood flow to organ

29

Neural controls

- vasoconstrictors: sympathetic nerves that release norepi
- vasodilators: neurons that release nitric acid

30

Hormonal controls

- vasocontrictors: epinephrine, angiotensin II, vasopressin
- vasodilators: epinephrine atrial natriuretic peptide

31

Local controls

- vasocontrictors: internal blood pressure (myogenic response) Endothelin-1
- vasodilators: decrease in O2, K+, CO2, H+, osmolarity, adenosine, eicosanoids, bradykinin, substances released during injury, nitric oxide

32

All controls go to...

go into arteriolar smooth muscle, altering the arteriolar radius

33

Capillaries

- the smallest blood vessels
- where gas and nutrient exchange happens by diffusion out of the blood into the tissues (or back into the blood)
- from interstitial fluid/space into capillaries = reabsorption
- movement fluid out of capillaries into interstitial space = filtration

34

Anatomy of capillary network

- arterioles carry O2 blood into
- capillaries = primary site for microcirculatory exchange

35

Velocity of capillary blood flow

- velocity is slowest in capillary beds because they have a greater cross-sectional area
- slow velocity flow in capillaries

36

Diffusion of capillary walls

- down gradient
- rate is fastest for small molecules (Co2 and O2)
- O2 and glucose diffuse down into tissue cells
- CO2 diffuses down and out of tissues into capillary

37

Net filtration pressure

- fluid pressure in capillary is greater than fluid pressure in interstitial space outside
- fluid pressure gradient promotes filtration
- increase capillary pressure = increase filtration
- decrease capillary pressure = decrease filtration
- increase concentration of solute particles = increase osmotic pressure = decrease water concentration
- decrease solute concentration = decease osmotic pressure = increase water concentration

38

Blood distribution

- pulmonary circulation = 12%
- heart = 9%
- arteries = 11%
- arterioles and capillaries = 7%
- veins = 61%

39

Short term regulation of arterial pressure and volume

- involves regulation of cardiac output and peripheral resistance

40

Arterial Baroreceptors

- stretch receptors sense arterial pressure
- impulses from baroreceptors are carried into CNS
- increase in pressure, causes baroreceptors to stretch, increases afferent impulses, decreasing sympathetic outflow to heart, arterioles, and veins, and increases parasympathetic outflow to heart

41

Long-term arterial pressure

- circulatory and renal system cooperates to adjust extracellular fluid volume and blood volume to maintain arterial pressure
- increase arterial pressure, increase renal output of solute and water, decrease extracellular fluid and blood volume
- increase blood volume has same affect as above

42

Hemorrhage and other causes hypotension

- decrease stroke volume
- increase heart rate
- decrease cardiac output
- decrease mean arterial pressure
- increase total peripheral resistance

43

Upright posture and pressure

- pressure due to gravity = 80 mmHg
- causes blood to somewhat pool in lower limb arteries right after stand up
- reflexes quickly sustain normal

44

Exercise

- healthy stress on body
- blood flow goes to areas needed most
- decrease flow to brain, increase flow to muscle, same flow to heart, increase flow to skin, decrease flow to kidney and organs

45

O2 consumption and training

- cardiac output increases in trained vs untrained allowing for more work rate
- heart rate is lower for work rate in trained vs untrained
- stroke volume increases O2 consumption in trained vs untrained

46

Hypertension treatments

- diuretics
- beta-adrenergic receptors
- CA2+ channel blockers
- ACE inhibitors
- drugs

47

Diuretics

- increase urine output and decrease extracellular volume decreasing pressure

48

Beta-adrenergic receptors

- decrease in heart rate and decrease CO and pressure

49

CA2+ channel blockers

- decrease smooth muscle contraction and lower peripheral resistance

50

ACE Inhibitors

- decrease overall activity of angiotensin system

51

drugs

- reduce sympathetic mediated stimulation

52

Heart Failure

- the greater the degree of cardiac filling, the greater the stroke volume, and cardiac output
- the greater cardiac failure, the greater the expansion of extracellular fluid volume, the greater filling pressure end diastolic volume
- heart failure = stroke volume much less at rest

53

Coronary Artery Disease and heart attacks

- adequete blood flow to heart is essential
- if flow through vessels is down, O2 needs is not met, and may create heart attack
- atherosclerosis (plaque build up) largest risk factor
- treated via drugs, dilate arteries and veins, drugs that reduce sympathetic NS, drugs that decrease clotting, drugs that control cholesterol
- stents also used to treat if necessary

54

Eurythrocyte

- red blood cell
- bi-concave disk
- excess surface area
- allows for flexibility and traveling
- 100-120 lifespan days

55

RBC production

- iron absorbed via GI tract and enters plasma
- transfaren distributes iron around body and to bone marrow
- when blood cells leave, iron stays in spleen
- lack of iron = decrease RBC production = anemia
- circulates = 3 months
- regulation of eurythiopoetin = negative feedback

56

Hemostasis

- preserve integrity of cardiovascular system and prevent blood loss

57

Role of liver

- synthesizes bile salts, absorbs vit K, synthesizes clotting factors, allows clotting factors to enter blood

58

Anticlotting systems

- endothelial cells (thrombin and protein C) and plasminogen activators (plasmin and fibrin)