openstax: chapter 20 chapter 21 blood vessels and circulation

BIOL 2402 Ch 21 Martini_10th Opensax_2013

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Openstax: Chapter 20

Blood Vessels and Circulation

Martini: 21-1 Types of Blood Vessels, pg. 724 Openstax: 20.1 Structure and Function of Blood Vessels, pg. 848

1. What is the function of blood vessels? deliver blood to ______________________________

____________________________________________________________________________ 2. List the five types of blood vessels:

a) ____________________________

b) ____________________________

c) ____________________________

d) ____________________________

e) ____________________________

2a. The vital functions of the cardiovascular system depends entirely on which blood vessel?

Chapter 21 Learning Outcomes

After completing Chapter 21, you will be able to:

1. Distinguish among the types of blood vessels based on their structure and function.

2. Explain the factors regulating blood flow, including autoregulation, neural and hormonal regulation. 3. Describe the forces that account for capillary exchange.

4. Know and label the major blood vessels of the systemic and pulmonary circulation. 5. Compare fetal circulation to that of an individual after birth.

Chapter 21

Learning Outcome 1: distinguish among the types of blood vessels based on their structure and function.

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3. Describe briefly the function for each type of blood vessel: 3a. Arteries: carry blood ___________________________________________________

3b. Arterioles: ___________________________________________________________

3c. Capillaries:

3d. Venules: collecting blood from _________________________________________

3e. Veins:

Basic Structure of a Blood Vessel 1. The walls of arteries and veins are composed of three layers (or tunics): a) ___________________________________ or __________________________________

b) ____________________________________________________

c) ___________________________________ or ___________________________________

Circle One: Which blood vessel has a thicker wall? A) artery B) vein

What is the lumen of a blood vessel?

Artery Vein


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2. Comparing a typical artery to a typical vein:

Fill in:

Tunica Location Tissue types Function

Interna (Intima)

Media

Externa (Adventitia)

Differences between Arteries and Veins: 1. Arteries and veins supplying the same region lie _________________________.

2. _____________ have thicker walls and higher blood pressure.

3. Compare the lumen of an artery vs. lumen of a vein:

Tunica externa Tunica media

Tunica interna

Tunica externa Tunica media

Tunica interna

Lumen of vein

Lumen of artery

ARTERY VEIN

Martini: Fig. 21-1 Openstax: Fig. 20.3


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4. Arteries are ____________________ 5. Veins (mainly in the limbs) have ____________ REVIEW QUESTIONS: 1. Are arteries elastic and contractile (contract and change their diameter)? A) Yes B) No 2. Circle One: Are arteries more muscular than veins? A) Yes B) No 3. Which layer of the vessel wall is thicker in arteries?______________________________ 4. Circle One: because arteries are more muscular than veins, what is the shape of arteries when: a) empty? 1. round 2. Square 3. Flat b) in tissue sections? 1. Flat 2. Triangular 3. Circular 5. Which type of blood vessel has venous valves? 6. Which layer of the heart wall gives rise to venous valves? 7. Why arteries have a thicker wall when compared to veins? 8. List the layers of an artery and describe the type of tissue/tissues that each one is made of. 9. List the layers of a vein and describe the type of tissue/tissues that each one is made of.


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Structure and Function of Arteries 1. are elastic and contractile. The tunica media (made of smooth muscle): 2. From the heart to peripheral capillaries, arteries change: a) from ____________________________

b) to ______________________________

c) to ______________________________

ELASTIC ARTERIES A. Also known as _______________ arteries B. The largest and closest arteries to the heart: C. Have high amounts of ______________ ________________________________ During ventricular systole elastic arteries: __________________________________ During ventricular diastole elastic arteries: _________________________________

MUSCULAR ARTERIES A. Also known as ______________ arteries B. Most common size of artery in the body. C. The smooth muscle layer (tunica media): Their thick tunica media allows muscular arteries to ______________________ _______________________________

ARTERIOLES A. Smallest type of artery. B. Have: C. Main site for both:


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Structure and Function of Blood Capillaries 1. Blood capillaries are the ONLY ______________________

_______________________________________________

_______________________________________________ 2. Describe the composition of a typical (common) blood capillary wall: Consists of _______________________________________ Average diameter of a blood capillary: 3. Types of blood capillaries:

a) _______________________________

b) _______________________________

c) _______________________________

Continuous capillaries 3a. 3b. Have a continuous ____________________________

__________________________________________ 3c. List substances that cannot pass through continuous capillaries: Fenestrated Capillaries 3d. Endothelial cells have many _____________________________ 3e. List molecules passing through fenestrations: 3f. List organs that contain fenestrated capillaries:

Arteriole

Venule

Continuous Capillary

See Fig. 21.4

capillaries

capillaries

Continuous Capillary

Martini: Fig. 21-3

Os: Fig. 20.5

Fenestrated Capillary


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Sinusoids (sinusoidal) capillaries 3g. Endothelial cells are separated by ___________________________ 3h. List substances that pass through sinusoids: 3i. List organs that have sinusoids: Structure and Function of Venules and Veins Venules 1. Are _________________________________ 2. Receive blood from ____________________ 3. Have: 4. Main place (along with blood capillaries) for ____________________________________ Medium-Sized Veins 1. Medium veins in the limbs have: ______ ________________________________ 1a. Venous valves are folds of tunica ________

Sinusoids

Function of venous valves:


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Large Veins 1. Have __________________________________________________________ Intact tunica ________________________ Thick tunica ________________________ Thin tunica _________________________ -Examples of large veins: Openstax: Table 20.2

Comparison of Arteries and Veins

Arteries Veins

Direction of blood flow

Conducts blood away from the heart Conducts blood toward the heart

General appearance Rounded Irregular, often collapsed

Pressure High Low

Wall Thickness Thick Thin

Oxygen Concentration Higher in systemic arteries Lower in pulmonary arteries

Lower in systemic veins Higher in pulmonary veins

Valves Not Present Present in meium-sized veins of the limbs

Distribution of Blood 1. Percent of blood volume in Heart, Arteries, Capillaries: ______ percent (about 1.5 liters) 2. Percent of blood volume in the Venous System: ______ percent (about 3.5 liters) 3. Why are veins regarded as capacitance vessels of the cardiovascular system?


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Martini: 21-2 Pressure and Resistance, pg. 734 Openstax: 20.2 Blood Flow, Pressure, and Resistance, pg. 860

Principles of Blow Flow 1. Constant blood flow ________________________________________________________

_________________________________________________________________________

1a. Blood flow = 2. What is blood flow? 3. What is the total blood flow at rest? Total blood flow at rest is equal to ____________________________________________ Review from Ch 20: What is cardiac output? Volume of blood _______________________ _________________________________________________________________________ Calculating CO: 4. Distribution of blood flow (F) to a tissue depends on _______________ and ______________

-F is proportional to P/R F = flow

P = pressure difference R = resistance

Learning Outcome 2: Explain the factors regulating blood flow, including autoregulation, neural and hormonal regulation. neural and hormonal regulation .


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Pressure Gradient (∆P) 1. Pressure gradient it the difference between ___________________________________ 2. The largest pressure gradient is found between _______________________________________ 3. What is blood pressure (BP)? 3a. Blood pressure is usually measured at the ____________ artery. 3b. Two pressures are recorded: 3c. List the normal and abnormal blood pressure values:

Label: brachial artery


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3d. Blood pressure changes relative to distance from the heart: 4. Preventing excessive blood pressure is clear! 4a. Describe one of the body’s chief mechanisms to prevent excessive blood pressure: The ability of arteries to ________________________________________________

____________________________________________________________________

4b.What is the importance of arterial elasticity? Expansion and recoil of arteries maintains ___________________________________

_____________________________________________________________________

_____________________________________________________________________

4c. Why does blood pressure (BP) increases with age? Arteries are ___________________________________________________________

_____________________________________________________________________

Vascular Resistance 1. What is vascular resistance? 1a. Three factors affect vascular resistance: Blood Viscosity 1a. What is blood viscosity? 1b. List the main factors that affect blood viscosity:


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1c. Choose one: a. Deficiency of erythrocytes (anemia) increases/decreases blood viscosity b. Decrease in blood viscosity increases/decreases speed of blood flow c. deficiency in albumin (hypoproteinemia) increases/decreases blood viscosity d. dehydration increases/decreases blood viscosity e. dehydration increases/decreases speed of blood flow f. Leukemia increases/decreases blood viscosity g. Leukemia increases/decreases speed of blood flow Vessel Length 1. How does length of a blood vessel influences blood flow? Vessel Diameter (size of the lumen) 1a. Blood traveling in a blood vessel exhibits smooth silent flow called _________________________ 1b. Describe laminar flow: 1c. Vasodilation (widening or dilation of vessel) -Describe what occurs to resistance to blood flow and blood speed when a vessel dilates: 1d. Vasocontriction (narrowing or contriction of vessel) -Describe what occurs to resistance to blood flow and blood speed when a vessel constricts:

Vasodilation

Vasoconstriction


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Which of these is the most immediate adjustable resistance factor to change blood flow? a) blood viscosity b) vessel length c) vessel diameter

Martini: Capillary Exchange, pg. 739 Openstax: 20.3 Capillary Exchange, pg. 869

Dilated arteriole

Constricted arteriole

Learning Outcome 3: Describe the forces that account for capillary exchange. .

Arteriole Venule


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1. The most important processes that move substances across common capillary wall are: Diffusion: net movement of substances from an area where their concentration is _____

________________________________________________________________ 2. At the arteriolar end of a blood capillary:

Arteriole Venule


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3. At the venule end of the capillary: Review some concepts from Chapter 21 by doing the review questions posted in EO2

Arteriole Venule

openstax: chapter 20 chapter 21 blood vessels and circulation

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