RT208 - CIRCULATORY SYSTEM

THE CIRCULATORY SYSTEM

System of blood vessels that, along with the heart, form the closed systems by which blood is circulated to all parts of the body.

• Pulmonary Circulation

• Systemic Circulation

Two types of CIRCULATORY CIRCULATION:

PULMONARY CIRCULATION

Carries blood from the RV of the heart to the lungs to remove carbon dioxide & pick up oxygen and returns oxygenated blood to the LA of the heart.

SYSTEMIC CIRCULATION

Serves the rest of the body, carrying oxygenated blood and nutrients from the LV of the heart to the body cells & returning to the RA of the heart with blood that is carrying carbon dioxide & other waste products of metabolism from the cells.

BLOOD VESSELS

Tube-like structures capable of expanding and contracting

• Carries blood

• RV (Right Atrium)

• heart to the lungs

• carbon dioxide

• pick up oxygen

• oxygenated blood

• LA (Left Atrium)

PULMONARY CIRCULATION:

____________ from the ____ of the ________________ to remove _____________________ & _______________ and returns _______________ to the ___ of the heart.

• rest of the body

• oxygenated blood

• nutrients

• LV (Left Ventricle)

• heart to the body cells

• RA (Right Atrium)

• carbon dioxide

• other waste products of metabolism

SYSTEMIC CIRCULATION:

Serves the ______________, carrying ________________ and __________ from the _____ of the ___________________ & returning to the ____ of the heart with blood that is carrying _______________ & ___________________ from the cells.

• Arteries

• Veins

• Capillaries

3 TYPES OF BLOOD VESSELS:

Arteries

• Blood vessels that carry blood away from the heart.

• Thick walled

• The pressure creates a pulse that can be felt, distinguishing them from veins.

• Systemic arteries carry oxygenated blood away from the heart to the tissues.

• Since its oxygen rich, full of oxygen, normal systemic arterial blood is bright cherry red.

• away

• Thick walled

• pressure, pulse, felt, veins

• Systemic arteries

• oxygen rich, full of oxygen, normal systemic arterial blood, bright cherry red.

ARTERIES

• Blood vessels that carry blood _______ from the heart.

• _________

• The ___________ creates a ______ that can be _____, distinguishing them from ______.

• ______________ carry oxygenated blood away from the heart to the tissues.

• Since its ___________, ___________, ________________________ is _____________.

• Lots of oxygen

• Lots of Carbon Dioxide / CO2

BRIGHT RED =

DARK RED =

PULMONARY ARTERY

only artery that carries deoxygenated blood.

• Pulmonary Artery

• Arterioles

• Aorta

ARTERIES consist of:

• pulmonary circulation

• deoxygenated blood

• heart

• lungs

• away

PULMONARY ARTERY:

• It is part of the _________________ & carries _________________ from the ______ to the ______.

• It is classified as an artery because it carries blood ______ from the heart.

ARTERIOLES

Smallest branches of arteries that join with the capillaries

AORTA

Largest artery in the body

• Venules

• Vena Cava

• Great Saphenous Veins

VEINS consist of:

VENULES

Smallest veins at the junction of the capillaries

VENA CAVAE

Largest veins in the body

GREAT SAPHENOUS VEINS

• Longest veins in the body

• Superficial vein - to carry blood from the tissues near the skin’s surface in your feet and legs to the deep veins.

• Runs the length of the leg

Superficial vein

to carry blood from the tissues near the skin’s surface in your feet and legs to the deep veins.

• Longest veins

• Superficial vein - tissues - skin’s surface - feet - legs - deep veins

• leg

GREAT SEPHENOUS VEINS

• ______________ in the body

• ______________ - to carry blood from the ________ near the _________ in your _____ and ____ to the ____________.

• Runs the length of the _____

CAPILLARIES

• Microscopic

• One-cell-thick vessels connect the arterioles & venules

• Forms a bridge between the arterial & venous circulation

• Microscopic

• One-cell-thick vessels, arterioles, venules

• bridge, arterial, venous circulation

CAPILLARIES

• ____________

• ________________ connect the ___________ & ___________

• Forms a _______ between the ________ & ______________

• venous

• arterial blood

Blood in the capillaries is a mixture of both _______ and ____________.

• Vital functions - cardiovascular system - events - capillary level.

• chemical - gaseous exchange - blood - interstitial fluid - capillary walls

The Anatomy of Blood Vessels

• ______________ of _______________________ depend entirely on __________ at ________________

• All ___________ & ___________ between ________ & ___________ takes place across __________.

• Ensures that plasma & interstitial fluid (2 major components of extracellular fluid) are in constant communication

• Accelerates distribution of nutrients, hormones, & dissolved gases throughout tissue

• Assists in transport of insoluble lipids & tissue proteins that cannot enter circulation by crossing capillary wall

• Has flushing action that carries bacterial toxins & other chemical stimuli to lymphoid tissues & organs responsible for providing immunity from disease
  
  SIMPLE TERMS:

• Communication

• Distribution

• Transport

• Immunity

The Anatomy of Blood Vessels

IMPORTANT FUNCTIONS:

• Tunica Interna

• Tunica Media

• Tunica Externa

WALLS OF ARTERIES & VEINS CONTAIN THREE DISTINCT LAYERS:

TUNICA INTERNA

• Innermost layer of blood vessel

• Includes endothelial lining & underlying layer of connective tissue with variable number of elastic fibers

internal elastic membrane

In arteries outer margin of interna contains thick layer of elastic fibers called?

• Innermost layer

• endothelial lining - connective tissue - elastic fibers

TUNICA INTERNA

• _______________ of blood vessel

• Includes ___________________ & underlying layer of ______________ with variable number of ____________

TUNICA MEDIA

• Middle layer containing concentric layers of smooth muscle tissue in framework of connective tissue

• Collagen fibers bind media to interna & externa

• Commonly thickest layer in wall of small artery

• Separated from surrounding externa by external elastic membrane: thin band of elastic fibers

• Smooth muscle cells encircle endothelium lining of lumen of vessel

• Middle layer - concentric layers - smooth muscle tissue - connective tissue

• Collagen fibers - interna - externa

• thickest layer - small artery

• external elastic membrane

• endothelium lining - lumen - vessel

TUNICA MEDIA:

• ____________ containing ______________ of _____________ in framework of ________________

• ____________ bind media to ________ & ________

• Commonly _____________ in wall of __________

• Separated from surrounding externa by ________________________ : thin band of elastic fibers

• Smooth muscle cells encircle _______________ of _______ of _______

TUNICA EXTERNA

• Outermost layer of vessel & forms connective tissue sheath around vessel

• In arteries, this layer contains collagen fibers with scattered bands of elastic fibers

• In veins, which is generally thicker than media, contains networks of elastic fibers & bundles of smooth muscle cells

• Outermost layer - connective tissue sheath

• arteries - collagen fibers - scattered bands - elastic fibers

• veins - thicker - elastic fibers - smooth muscle cells

TUNICA EXTERNA

• _______________ of vessel & forms __________________ around vessel

• In ________, this layer contains ___________ with _______________ of __________

• In _______, which is generally ________ than media, contains networks of ____________ & bundles of __________________

• Have thicker walls

• Have more smooth muscle and elastic fibers

• More resilient

COMPARED TO VEINS, ARTERIES:

• Walls - Arteries - Thicker - Veins

IN GENERAL:

1. _____ of ________ are ________ than ______

• Tunica media - artery - more

• resist pressure - forces blood

IN GENERAL:

2. ___________ of _______ contains ______ smooth muscle & elastic fibers

• These contractile & elastic components ____________ generated by heart as it ___________ into circuit.

• blood pressure - elastic fibers - recoil - constricting lumen - smaller - circular shape

IN GENERAL:

3. When not opposed by ____________, ___________ in arterial walls _______, ______________ so arterial walls on slide look ________ than veins, but they retain _______________

Veins

IN GENERAL:

4. _______ do not retain circular shape

Endothelial lining - endothelium - folds - pleated - lining of vein

IN GENERAL:

5. ______________ of artery cannot contract, its _____________, is thrown into _____ that give arterial sections a _________ appearance, ____________ lacks these folds

• Elastic Arteries

• Muscular Arteries

• Arterioles

• Capillaries

• Venules

• Medium Veins

• Large Veins

BLOOD FLOWS THROUGH THE BLOOD VESSELS FROM THE HEART AND BACK TO THE HEART IN THE FOLLOWING ORDER:

ELASTIC ARTERIES

• conducting arteries

• large vessels that transport large volumes of blood away from heart walls are extremely resilient

• tunica media contains high density of elastic fibers & relatively few smooth muscle cells

• able to tolerate pressure changes that occur during cardiac cycle

• conducting arteries

• large vessels - large volumes - away - extremely resilient

• tunica media - high density

• pressure changes - cardiac cycle

ELASTIC ARTERIES:

• _________________

• ______________ that transport ___________ of blood _____ from heart walls are ___________

• _____________ contains _________ of elastic fibers & relatively few smooth muscle cells

• able to tolerate _____________ that occur during _____________

• AORTA

• PULMONARY ARTERY

Example of ELASTIC ARTERIES:

MUSCULAR ARTERIES

• medium-sized arteries or distribution arteries

• distribute blood to body’s skeletal muscle & internal organs

• characterized by thick tunica media that contains more smooth muscle cells than does media of elastic arteries

• 0.5-10 mm in diameters

• medium-sized arteries - distribution arteries

• skeletal muscle - internal organs

• thick tunica media - more - media

• 0.5-10 mm

MUSCULAR ARTERIES

• ___________________ or ___________________

• distribute blood to body’s ______________ & _______________

• characterized by ________________ that contains ______ smooth muscle cells than does ______ of elastic arteries

• ________ in diameters

• EXTERNAL CAROTID ARTERIES (NECK)

• BRACHIAL ARTERIES OF ARMS

examples of MUSCULAR ARTERIES:

ARTERIOLES

• resistance vessels

• poorly defined tunica externa, & media of larger arterioles consists of one or two smooth muscle cells

• diameters change in response to local conditions or to sympathetic or endocrine stimulation

• resistance vessels

• poorly - tunica externa - media - larger arterioles - one - two

• diameters - local conditions - sympathetic - endocrine stimulation

ARTERIOLES

• ________________

• _______ defined ___________, & _______ of ________ consists of ___ or ____ smooth muscle cells

• __________ change in response to _______________ or to ____________ or _______________

CAPILLARIES

only vessels that allow exchange

VENULES

The 5th Blood Flow Stage:

MEDIUM VEINS

The 6th Blood Flow Stage:

• Vena Cava

• Pulmonary Vein

Examples of Large Veins:

• Pressure decreases

• Flow decreases

• Resistance increases

As blood flows from the aorta toward the capillaries and from capillaries toward the vena cava:

• Away - heart - aorta - 30 cm / sec

• Capillary beds - one thousand times - slower

• Blood flow _______ from the _______ in the _______, the blood travels at __________

• As it reaches the ___________, the rate of flow is dramatically (__________________) _______ than the rate of flow in the aorta.

ARTERIES

Undergo changes in diameter in order to increase or decrease the size of the artery.

• Vasoconstriction

• Vasodilation

ARTERIES Undergo changes in diameter in order to

increase or decrease the size of the artery:

VASOCONSTRICTION

Decreases the size of the lumen

VASODILATION

Increases the size of the lumen

capillary bed

Capillaries form networks called?

pre-capillary sphincter

Blood flow through the capillary is regulated by?

Precapillary sphincter

band of smooth muscle that guard’s entrance to each capillary

CAPILLARIES

The only blood vessels whose walls permit exchange between blood & surrounding interstitial fluids

• slow - sufficient time - diffusion - active transport

CAPILLARIES:

Blood flows through capillaries relatively _____, allowing ____________ for __________ or _____________ of materials across walls

endothelial tube - delicate basement membrane

Typical capillary consists of ________________ inside ____________________

tunica media nor externa

CAPILLARIES Has neither _________________

• CONTINUOUS CAPILLARY

• FENESTRATED CAPILLARY

• SINUSOIDAL CAPILLARY

Capillaries have two (Three) basic structures:

CONTINUOUS CAPILLARY

• Have complete lining

• Supply most region of body

• Can be found in all tissues except epithelial and cartilage

• Least permeable, most common (skin & muscle)

• complete lining

• most region

• all tissues - epithelial - cartilage

• Least permeable - skin & muscle

CONTINUOUS CAPILLARY

• Have _____________

• Supply __________ of body

• Can be found in __________ except __________ and _________

• ___________, most common (___________)

FENESTRATED CAPILLARY

• Contain windows (pores) that span endothelial lining

• Permit rapid exchange of large solutes

• Occurs in areas of active absorption or filtration (kidneys, small intestine)

• Flattened fenestrated capillaries = sinusoids

• windows - pores - endothelial lining

• rapid - large solutes

• active absorption - filtration - kidneys, small intestine

• sinusoids

FENESTRATED CAPILLARY

• Contain ________ (______) that span _______________

• Permit ______ exchange of _________

• Occurs in areas of ____________ or _________ (________, ___________)

• Flattened fenestrated capillaries = __________

SINUSOIDAL CAPILLARY

• specialized fenestrated capillaries that are flattened & irregular

• blood moves through sinusoids relatively slowly, maximizing time available for absorption & secretion across sinusoidal walls

• most permeable

• occurs in special locations (liver, bone marrow, adrenal glands, spleen)

• specialized fenestrated capillaries - flattened - irregular

• sinusoids - slowly - absorption - secretion - sinusoidal walls

• most permeable

• liver - bone marrow - adrenal glands - spleen

SINUSOIDAL CAPILLARY

• ______________________ that are _________ & _________

• blood moves through __________ relatively _____, maximizing time available for __________ & _______ across ____________

• _____________

• occurs in special locations (_____, __________, __________, ______)

VEINS

Collects blood from all tissues and organs and return it to the heart

• Venules

• Medium-sized veins

• Large veins

Veins are classified according to their size into:

• Venules

• Medium-sized Veins

veins that contain valves

Valves

prevent backflow of blood

• pressure - heart - blood - arteries

VEINS

The __________ created by the _____ pushes the ______ thru the _________.

• arteries - directly related - patient’s blood

The pressure inside the _________ is _______________ to the _____________ pressure.

very low

The pressure in the veins is ___________.

• high pressure

• low pressure

• ARTERIES =

• VEINS =

• SUPERFICIAL VEINS

• DEEP VEINS

TWO TYPES OF VEINS:

SUPERFICIAL VEINS

• show considerable individual variation

• subcutaneous in the fasciae and are easily palpable

• considerable

• subcutaneous - fasciae - palpable

SUPERFICIAL VEINS

• show ____________ individual variation

• _____________ in the ________ and are easily ________

• Cephalic Vein

• Basilic Vein

• Median Vein

TYPES OF SUPERFICIAL VEINS:

Cephalic Vein

in the dorsal venous network on the dorsum of the hand (radial aspect)

Basilic Vein

in the dorsal venous network and ascends along the posterior ulnar side of the wrist

Median Vein

drains the palmar venous arch

DEEP VEINS

• accompany arteries

• usually in pairs on either side of the artery and are connected by short crosslinks

• not advised for use for routine IV access due to their close proximity to arteries and veins

• arteries

• pairs - short crosslinks

• not advised - routine IV - close - arteries - veins

DEEP VEINS

• accompany ________

• usually in ______ on either side of the artery and are connected by ____________

• ___________ for use for _________ access due to their ______ proximity to ________ and ______

Radial vein

run alongside the radial artery

Ulnar vein

run alongside the ulnar artery

• Aneurysm

• Arteriosclerosis

• Atherosclerosis

• Embolism

• Embolus

• Hemorrhoids

• Phlebitis

• Thrombophlebitis

• Thrombus

• Varicose Veins (Varices)

VASCULAR SYSTEM DISORDERS:

Varices

Varicose Veins are also called?

ANEURYSM

A localized dilation or bulging in the wall of a blood vessel, usually an artery

ARTERIOSCLEROSIS

Thickening, hardening, and loss of elasticity of artery walls

ATHEROSCLEROSIS

A form of arteriosclerosis involving changes in the intima of the artery due to accumulation of lipids and so on

EMBOLISM

Obstruction of a blood vessel by an embolus

EMBOLUS

Air, mass of undissolved matter circulating in the bloodstream