Vascular Disorders and Thrombosis

what do organisms require to maintain homeostasis

circulatory system

what is the main function of the circulatory system

deliver nutrients and remove waste products from cells

what is the purpose of lymphatics

drain the extracellular space

arteries are under

high pressure

arteries move blood

away from the heart

veins move blood

towards the heart

the circulatory system is composed of

blood

central pump (heart)

vascular network

lymphatic vessels empty back into the blood via

thoracic duct

arteries have

large lumen

thick vessel walls

why is it important for arteries to have thick vessel walls

must withstand large pressure and stretch/recoil to keep continuous flow of blood

what do the artery vessel walls have in them

tensile (strength)

elastin (elasticity)

t/f arteries have large resistance to blood flow due to having a large lumen

false, minimal resistance

arterioles have

narrow lumen

thick layer of smooth muscle

what is important about the smooth muscle in arterioles

constricts based on sympathetic/ parasympathetic stimulation

what is the main function of the narrow lumen in arterioles

provide resistance to circulatory system as blood moves further from heart

what are the three layers of vessels

tunica intima, tunica media, tunica adventitia

what is the function of capillaries

site of nutrient waste/ product exchange between blood and surrounding tissue

t/f capillaries are the most numerous vessel but only contains 5% of total blood volume

true

what are the three types of capillaries

continuous, fenestrated, discontinuous

RBC moving through capillaries single file allows for

time for exchange of nutrients and waste

what allows RBC to move single file through capillary

slow velocity of blood flow

small lumina

continuous capillaries have

continuous endothelium

basement membrane

what is the function of continuous capillaries

passage of small molecules

exchange of oxygen and carbon dioxide

where can continuous capillaries be found

brain

lung

muscle

bone

fenestrated capillaries have

discontinuous endothelium

continuous basement membrane

what is the function of fenestrated capillaries

exchange of slightly large products

basement membrane being continous in fenestrated aids in

keeping certain products within the lumen due to negative charge

fenestrated capillaries are found in

renal glomeruli

intestinal villi

endocrine glands

chorid plexus

ciliary body of eye

discontinuous capillaries have

discontinuous endothelium and discontinuous basement membrane

what is the function of discontinuous capillaries

maximum passage of molecules from vascular lumen to extracellular space

discontinuous capillaries are found in

liver

spleen

bone marrow

veins are composed of

collagen, little smooth muscle and elastin

veins have

thinner vascular wall

blood passage through veins depends on

valves to prevent backflow

contraction on skeletal muscle

increased pressure gradient

veins typically ___ rather than contract

distend

veins typically hold how much of the total blood volume

65%

what is the purpose of elastin

gives elasticity to vessels

what is being shown on the right **

artery

what is being shown on the left **

vein

which layer of the vessel is the endothelium with elastin

tunica intima

which layer of the vessel is the smooth muscle

tunica media

which layer of the vessel is the connective tissue

tunica adventitia

lymphatic vessels have

overlapping endothelial cells with large interendothelial gaps

t/f lymphatic vessels are distensible and a low pressure system like arteries

false, like VEINS

what is required to move lymph through lymphatic system

valves

contraction of skeletal muscle

what is the function of endothelium

fluid distribution

inflammation

immunity

agiogenesis

hemostasis

normal endothelium is

antithrombotic and profibrinolytic

what does antithrombotic mean

regulates hemostasis and prevents clot formation

what does profibrinolytic mean

helps break down complexing of fibrinogen into fibrin

single layer of endothelial cells lines

all components of the circulatory system

what is rete mirabile

specialized vascular networks formed by arterial blood vessels through center of large venous sinuses

what is the function of rete mirabile

countercurrent exchanger

-regulate temp

-ionic contraction gradients

-O2/CO2 exchange

-equalize blood pressure

where are rete mirabile located

around right and left internal carotid arteries

along cranial floor

what is the interstitium

space between parenchymal and stromal cells and microcirculation

what is the function of the intersitium

provide pathways for microvasculature, lymphatic vessels, nerves, and trafficking leukocytes

module systemic physiologic properties exerted by parenchymal glands

general fluid pool providing cushioning effects for organs

structural framework for cell survival

what is the extracellular matrix

structural, adhesive, and absorptive components WITHIN the interstitium

ECM is composed of

type I collagen

glycoproteins

glycosaminoglycans

proteoglycans

type I collagen provides

structural framework for ECM

what do glycoproteins provide for ECM

sites of attachment for structural proteins

site of adhesion for transmigrating leukocytes

what do proteoglycans do for the ECM

hydrophilic, bind to large amounts of water

components of the ECM are produced by

parenchymal cells

fibroblasts

glial cells (CNS)

macrophages

trafficking leukocytes