vascular system part one - amazon s3 · 2016-11-15 · objectives summarize how cardiac output,...
TRANSCRIPT
Vascular System
Part One
Objectives Trace the route taken by blood as it leaves, and then
returns to the heart.
Describe the structure of the walls of arteries and veins.
Discuss the structure and function of the three classes of arteries.
Describe the characteristics that make veins distinct from arteries.
Discuss the structure and function of the three classes of veins.
Describe the structure, function, and organization of capillaries.
Blood Vessel Layers
Tunica intima
Tunica media
Tunica externaLumen
Blood Vessel Layers Tunica intima
Innermost layer
Consists of endothelium
Same as endocardium that lines hearts
Smooth surface keeps blood flowing freely
Prevents clots
Chemicals that cause blood vessels to
Dilate
Constrict
Blood Vessel Layers Tunica media
Middle layer
Smooth muscle
Innervated by autonomic nervous system
Elastic tissue
Allows blood vessel to change in diameter
Blood Vessel Layers Tunica externa
Outer layer
Strong and flexible
Fibrous connective tissue
Supports and protects
Aneurysm Portion of the vessel wall has weakened
Causing the blood to balloon out
Types of Blood Vessels• Arteries:
• Carry blood away from the heart
• Arteries = Away
• Veins:
• Return blood to the heart
• Capillaries:
• Connect the smallest arteries to the smallest veins
• Capillaries= Connect
• Sites for exchange of nutrients and oxygen
Categories of Arteries Conducting arteries
elastic arteries
• Distributing arteries • muscular arteries
• Arterioles• resistance vessels
Categories of Arteries Largest
Closest to the heart
Branch and divide
Grow smaller as they travel away
Categories of Arteries Conducting Arteries
Expand as blood surges into the them
Greatest ability to expand and recoil
Recoil when ventricles relax
Examples:
Aorta
Carotids
Categories of Arteries Distributing Arteries
Carry blood to specific organs and areas of body
Examples:
Brachial
Femoral
Renal Arteries
Categories of Arteries Aterioles
Smallest arteries
Contraction of smooth muscle in walls
Resist flow of blood to regulate BP
Control blood flow to an organ
Veins Become smaller as they lead away from the
heart
Converge from smaller to larger
Have thinner walls than arteries
Not as much pressure
Have a great ability to stretch
Can constrict extensively
Veins Capacitance Vessels
Stretch
Carry varying amounts of blood
Little to no change in pressure
Constrict extensively
Helps maintain BP
Blood volume drops
Categories of Veins Venules
Medium-sized veins
Large veins
Categories of Veins Venules
Smallest veins
Collect blood from the capillaries
Thin, porous walls
Exchange fluid with surrounding tissues
Categories of Veins Medium-sized veins
Convergence of venules
Thicker, more elastic walls
One-way valves to prevent black flow
Example:
Radial and Ulnar Veins
Categories of Veins Large Veins
Convergence of medium-sized veins
Thick tunica externa
Examples:
Vena Cavae
Pulmonary Veins
Capillaries
Microscopic vessels that link
Aterioles and venules
Are the exchange vessels
Nutrients
Waster
Hormones
Transfer between blood and tissue
Have extremely thin walls
Have very small diameters
Capillaries Tissue with high metabolic rates
Liver
Kidneys
Myocardium
Large number of capillaries
Capillaries Fibrous Connective Tissues
Lower metabolic rates
Tendons
Few capillaries
Capillaries Epidermis
Cartilage
Lens of Eye
Cornea of Eye
No capillaries
Question
Veins are called capacitance vessels because:
A. they can constrict extensively.B. they can stretch.C. they convey blood back to the heart.D. they contain one-way valves.
Capillary Organization
Exercise Rest
Capillary Organization Exchange vessels
Organized into network of capillary beds
Capillary Walls
Single layer of endothelium
Basement membrane
Capillary Organization Body does not contain enough blood to fill entire
system
Precapillary sphincter
Beginning of each network
Capillary Organization Exercise = more oxygen required
Sphincters open
Blood fills capillary network
Exchange occurs
Rest= oxygen not required
Blood bypasses capillary bed
Flows into venule
Quiz Review Know your Matching Worksheet
Know which blood vessel connect 2 sides of vascular system
Know how capillaries are organized
Know what conducting arteries are and how they function
Know what the tunica intima is its function
Know the correct order of vessels in arterial system
Homework Read Chapter 15
Review the Animations on the Davis Website Student Resources
Use the flashcards to prepare for QUIZ
House Call Due 11-22-2016
Quiz 11-22-2016
Test 11-23-2016 Chapter 15 Only
Workbook due 11-23-2016
Lab Presentations 11-23-2016 following TEST
Vascular System
Part Two
Objectives Explain the methods of
Capillary exchange
Diffusion
Filtration
Colloid osmotic pressure.
Identify and explain the three main causes of edema.
Trace the path of pulmonary circulation.
Capillary Organization Sinusoid
Unique capillary
Liver, bone marrow, spleen
Irregular, blood-filled spaces
More permeable
Allow for the passage of large substances
Blood
Proteins
Capillary Exchange
Walls allow for two-way exchange
Capillary Exchange Mechanisms of exchange
Diffusion
Filtration
Osmosis
Diffusion
Capillary Exchange Mechanisms of exchange
Diffusion
Most important mechanism of capillary exchange
Greater to lesser concentration
Release chemicals to surrounding tissues
Oxygen
Carbon Dioxide
Glucose
Hormones
Nutrients
Filtration
Filtration Filtration
Occures close to the arterial side of capillary bed
Metarteriole
Pressure 30-35 mm Hg
Tissue
2 mm Hg
Pushes dissolved nutrients
Plasma
Glucose
Amino Acids
Colloid Osmotic Pressure
View animation on “Mechanisms of capillary exchange”
Colloid Osmotic Pressure Osmosis
Blood moves toward venous end of capillary
Blood Pressure inside capillary drops
10 mm Hg
Drop in pressure allows:
Proteins to exert colloid osmotic pressure
Albumin pulls tissue fluid and waste
Into capillaries
QuestionHow does the cardiovascular system meet the metabolic
needs of skeletal muscle during strenuous exercise?
A. It maintains blood flow at stable rate.
B. It opens up capillary beds in skeletal muscle.
C. It temporarily diverts blood from the GI trace and brain to get extra blood to muscles.
D. It dilates capillaries to approximately twice their original diameter to accommodate the extra blood.
Edema Fluid filters out of capillaries faster than it is
reabsorbed
Accumulation in tissues
3 Main Causes
Increased capillary filtration
Reduced capillary reabsorption
Obstructed Lymphatic drainage
Edema Increased Capillary Filtration
Capillary pressure drives filtration
Rise = Rise
Causes
Kidney failure
Poor venous return
R sided ventricle failure
Edema Reduced capillary reabsorption
Deficiency in albumin
Slow reabsorption
Causes
Liver disease
Burns
Edema Obstructed lymphatic drainage
Absorbs 15% of fluid filtered by capillaries
Obstruction = fluid accumulation
Surgical removal
Pulmonary Circulation
View animation on “Pulmonary circulation”
Pulmonary Circulation Routes the blood to and from the lungs
Exchange of carbon dioxide and oxygen
Does NOT supply lung tissue with oxygen
Lung tissue is oxygenated through systemic circulation
Question
Capillaries release oxygen and take up carbon dioxide from surrounding tissues through the process of:
A. osmosis.B. filtration.C. diffusion.D. colloid osmotic pressure.
Test Review Reading- Chapter 15 Definitions to KNOW
Resistance Vessels
Siusoids
Metarterioles
Quiz Review Know your Matching Worksheet
Know which blood vessel connect 2 sides of vascular system
Know how capillaries are organized
Know what conducting arteries are and how they function
Know what the tunica intima is its function
Know the correct order of vessels in arterial system
Homework Read Chapter 15
Review the Animations on the Davis Website Student Resources
Use the flashcards to prepare for QUIZ
House Call Due 11-22-2016
Quiz 11-22-2016
Test 11-23-2016 Chapter 15 Only
Workbook due 11-23-2016
Lab Presentations 11-23-2016 following TEST
Vascular System
Part Three
Objectives Name the regions of the aorta and the major arteries
arising from each region.
Describe the blood supply to the head and neck.
Identify the principal veins of systemic circulation.
Discuss the principles of a pressure gradient and how it relates to blood pressure and circulation.
Pulmonary Circulation
View animation on “Pulmonary circulation”
Pulmonary Circulation1. Blood leaves the right ventricle through the pulmonary
trunk, which branches into the right and left pulmonary arteries.
2. The pulmonary arteries enter the lungs.
3. The pulmonary artery branches into lobar arteries (one for each lobe of the lung). These arteries branch into smaller and smaller arteries until ending at the capillary beds.
Pulmonary Circulation4. The capillaries surround the alveoli, where the
exchange of oxygen for carbon dioxide occurs.
5. The capillaries form venules, which merge to form veins. The veins merge until forming the pulmonary vein, which returns the oxygenated blood to the left atrium.
Systemic Circulation
Ascending aortaAortic arch
Descending aorta
Systemic Circulation Supplies oxygen and nutrients to organs
Removes waste
Systemic Circulation Arteries
Arise from aorta
3 regions Ascending aorta
Right and Left Coronary Arteries
Aortic Arch
Brachiocephalic
Left common carotid
Left subclavian
Descending aorta
Thoracic and abdominal cavities
Diaphragm divides
Thoracic aorta
Abdominal aorta Blood Supply to liver
Systemic Circulation Abdominal Aorta
Right common iliac artery
Right leg
Femoral
Popliteal
Left common iliac artery
Left leg
Femoral
Popliteal
Pulses
Pulses Radial
Most common site for routine assessment of heart rate
Carotid/Femoral
Common site during an emergency for assessment of heart rate
Principal Arteries
Subclavian artery
Axillary artery
Brachial artery
Radial artery
Thoracic aorta
Celiac trunk
Renal artery
Superior mesenteric artery
Inferior mesenteric artery
Common iliac artery
External iliac artery
Internal iliac artery Femoral artery
Popliteal artery
Anterior tibial artery
Posterior tibial artery
Dorsalis pedis artery
Arteries of the Head and Neck
Vertebral artery
Point at which carotid
artery branches
Common carotid
artery
Vertebral artery
Circle of Willis
Venous Circulation Body drains from organs and other parts
Brings all back to Vena Cava
Principal Veins
Internal jugular vein
Cephalic vein
Medial cubital vein
Popliteal veinGreat saphenous vein
Hepatic veins
Venous Circulation Vena Cava
Main Vein
Superior Vena Cava
Receives blood from above the heart
Head
Shoulders
Arms
Inferior Vena Cava
Receives blood from below the heart
Lower half of the body
Venous Circulation Superficial veins
Reside near surface
Deep veins
Deep well protected areas
Usually along side artery, nerve
Veins of the Head and Neck
Internal jugular vein
External jugular vein
Vertebral vein
Hepatic Portal Circulation
View animation on “Hepatic-portal circulation”
Inferior vena cava
Hepatic Portal Circulation Veins empty to portal vein
Portal vein empties into sinusoids Superior mesenteric vein converges here
Sinusoids empties into hepatic vein
Hepatic vein to inferior vena cava
Allows for removal of Toxins
Bacteria
ETOH
Storage of glycogen
Question
Portal systems allow blood to:
A. pass through two capillary networks before returning to the heart.
B. pass through one capillary network before returning to the heart.
C. bypass all capillary networks and return to the vena cava.
D. shunt blood from one vein to another.
Principles of Circulation
Principles of Circulation Pressure gradient
Blood moves away = pressure declines
Greater the difference in pressure = greater the flow
Resistance
The greater the resistance = lesser the flow
Kahoot.it
Quiz Review Know your Matching Worksheet
Know which blood vessel connect 2 sides of vascular system
Know how capillaries are organized
Know what conducting arteries are and how they function
Know what the tunica intima is its function
Know the correct order of vessels in arterial system
Homework Read Chapter 15
Review the Animations on the Davis Website Student Resources
Use the flashcards to prepare for QUIZ
House Call Due 11-22-2016
Quiz 11-22-2016
Test 11-23-2016 Chapter 15 Only
Workbook due 11-23-2016
Lab Presentations 11-23-2016 following TEST
Vascular System
Part Four
Objectives Summarize how cardiac output, blood volume, and
resistance affect blood pressure.
Explain the relationship between blood pressure, peripheral resistance and blood flow.
Discuss why blood flow through the capillaries is slower than any other part of the vascular system.
Describe the neural and hormonal regulation of blood pressure and flow.
Describe how the skeletal muscle pump and the respiratory pump aid in venous return.
Factors Affecting Blood PressureCardiac output ↑ CO = ↑ BP
↓ CO = ↓ BP
Blood volume ↓ Volume = ↓ BP↑ Volume = ↑ BP
Resistance ↑ Resistance = ↓ Flow and ↑ Pressure↓ Resistance = ↑ Flow and ↓ Pressure
Factors Affecting Blood Pressure Blood pressure is determined by
Cardiac output
Blood volume
Resistance
Factors Affecting Blood Pressure Cardiac output
Heart beats harder = increased cardiac output
Cardiac output increases = BP increases
CONVERSLY
Cardiac output decreases = BP decreases
Exercise stops
Heart is weak
Factors Affecting Blood Pressure Blood volume
Blood volume declines = BP Falls
Dehydration
Hemorrhage
Kidneys reduce urine output
Boost blood volume = BP Rises
Peripheral Resistance Friction of blood against walls of vessels
Peripheral vascular system
Diameter
Greatest influence on resistance
Blood
Viscosity
Peripheral Resistance Amount of friction depends upon
Blood viscosity
Greater the viscosity slower it flows
Vessel diameter
Greatest influence on resistance
Peripheral Resistance Force that must be overcome for blood to reach the
tissues.
Lower the peripheral resistance = lower the blood pressure
Necessary or system would collapse
BP must rise to overcome peripheral resistance
Critical Thinking BP declines as it moves away from the heart…
WHY?
Vasoconstriction
Vasodilation
Blood Velocity= Speed
Question
Which condition would you expect to accompany atherosclerosis, a disorder in which arteries lose elasticity and fatty material builds up inside the vessels?
A. Irregular heartbeatB. Low blood pressureC. Increased blood viscosityD. High blood pressure
Neural Regulation of Blood Pressure
• ↑ BP → Parasympathetic impulses → Vasodilation → ↓
BP
• ↓ BP → Sympathetic impulses → Vasoconstriction →↑ BP
View animation on “Neutral regulation of blood pressure (baroreceptors)"
Hormonal Regulation of Blood Pressure A number of hormones raise blood pressure.
Renin, angiotensin I, angiotensin II
Aldosterone
Antidiuretic hormone (ADH)
Epinephrine and norepinephrine
Atrial natriuretic peptide (ANP) causes blood pressure to fall.
Venous Return Fight the forces of gravity
Skeletal muscle
Respiratory pump
Venous ReturnRelaxed skeletal musclesContracted skeletal
muscles
Respiratory Pump
Kahoot.it
Homework Read Chapter 15
Review the Animations on the Davis Website Student Resources
Use the flashcards to prepare for QUIZ
House Call Due 11-22-2016
Quiz 11-22-2016
Test 11-23-2016 Chapter 15 Only
Workbook due 11-23-2016
Lab Presentations 11-23-2016 following TEST