The document summarizes key points about circulation and the cardiovascular system from Chapter 23 of Biology: Concepts & Connections. It discusses how circulatory systems facilitate exchange between tissues and the environment. Both open and closed circulatory systems are described. The evolution of the vertebrate heart from two-chambered to four-chambered designs is covered. Key aspects of the human cardiovascular system like blood flow through the heart and blood vessel structure and function are summarized.

1. Chapter 23
Circulation
PowerPoint Lectures for
Biology: Concepts & Connections, Sixth Edition
Campbell, Reece, Taylor, Simon, and Dickey
Copyright © 2009 Pearson Education, Inc.
Lecture by Richard L. Myers
Translated by Nabih A. Baeshen

2. MECHANISMS
OF INTERNAL TRANSPORT
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3. 23.1 Circulatory systems facilitate exchange with all body tissues
AAllll cceellllss nneeeedd
– Nutrients
– Gas exchange
– Removal of wastes
DDiiffffuussiioonn alone is inadequate for large and complex bodies
AAnn iinntteerrnnaall ttrraannssppoorrtt ssyysstteemm assists diffusion by moving
materials between
– Surfaces of the body
– Internal tissues
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4. 23.1 Circulatory systems facilitate exchange with all body tissues
A gastrovascular cavity in cnidarians
and flatworms serves in Digestion and
Distribution of substances
Circulatory system in most animals
consists of Blood, Heart and Blood vessels
Open circulatory systems in Arthropods
and many molluscs
– Heart pumps blood through open-ended
vessels
– Cells directly bathed in blood
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5. Pores
Tubular heart
The open circulatory system (vessels in gold) in a
grasshopper

6. 23.1 Circulatory systems facilitate exchange with all body tissues
Closed circulatory systems
– Vertebrates, earthworms, squids, octopuses
– Blood stays confined to vessels
– A heart pumps blood through arteries to
capillaries
– Veins return blood to heart
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7. Capillary beds
Artery
(O2-rich blood)
Arteriole
Venule
Artery
(O2-poor blood)
Heart
Atrium
Ventricle
Vein
Gill
Capillaries
The closed circulatory system in a fish

8. 23.2 EVOLUTION CONNECTION:
Vertebrate Cardiovascular
systems reflect evolution
Two-chambered heart
in fish pumps blood in a
single circuit From gill
Gill capillaries
Heart:
Ventricle (V)
capillaries To systemic
capillaries Back to heart
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Atrium (A)
Systemic capillaries

9. 23.2 EVOLUTION CONNECTION: Vertebrate Cardiovascular
systems reflect evolution
Double circulation in land vertebrates have Separate
pulmonary and systemic circuits
Three-chambered hearts
–Amphibians, turtles, snakes, lizards
– Two atria and one undivided ventricle
– Permits blood diversion away from lungs when diving
– But some blood from body and lungs mixes in the ventricle when not diving
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10. Lung and skin capillaries
Pulmocutaneous
circuit
A A
The double circulation and
three-chambered heart of an
V
Right Left
Systemic circuit
amphibian
Systemic capillaries

11. 23.2 EVOLUTION CONNECTION: Vertebrate Cardiovascular
systems reflect evolution
Four-chambered hearts
–Crocodilians, birds, mammals
–Two atria and two ventricles
–Two circuits that do not mix
– Right side pumps blood from body to lungs
– Left side pumps blood from lungs to body
–Higher blood pressure
– Supports more efficient movement of blood
– Needed in endothermic animals
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12. Lung capillaries
Pulmonary
circuit
A A
The double circulation
and four-chambered
heart of a bird or V
V
Right Left
mammal
Systemic circuit
Systemic capillaries

13. THE HUMAN
CARDIOVASCULAR
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SYSTEM

14. 23.3 The human cardiovascular system illustrates the double
circulation of mammals
Blood flow through the double circulatory system of humans
The mammalian heart consists of
– TTwwoo tthhiinn-wwaalllleedd aattrriiaa that
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move blood to ventricles
– TThhiicckk--wwaalllleedd vveennttrriicclleess that Pump blood to lungs and all other body
regions
–

15. Superior
vena cava
Pulmonary
artery
Capillaries
of right lung
8
9
2
3
Aorta
ورط ا
4 5
10
Pulmonary
artery
Capillaries
of left lung
3
2
7
Capillaries of
head, chest, and
arms
1
6
Pulmonary
vein
Right atrium 9
Right ventricle
Inferior
vena cava
4
8
Pulmonary
vein
Left atrium
Left ventricle
Aorta
Capillaries of
abdominal region
and legs
Blood flow through the double circulation of the human cardiovascular system

16. 23.4 The heart contracts and relaxes rhythmically
Cardiac output: Amount of blood/minute
pumped into systemic circuit
Heart rate: Number of beats/minute
Heart valves: Prevent the backflow of blood
Heart murmur: A defect in one or more
heart valves
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17. 23.5 The pacemaker sets the tempo of the heartbeat
The pacemaker (SA node in upper wall
of right atrium)
– Sets the rate of heart contractions
– Generates electrical signals in atria
The AV node
– Relays these signals to the ventricles
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18. 23.6 CONNECTION: What is a heart attack?
A heart attack is
damage to cardiac
muscle typically from
a blocked coronary
artery
Superiorvena cava
Pulmonary
Artery
Aorta
Left
coronary
Artery
Stroke Death of brain
tissue from blocked
arteries in the head
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Right
coronary
Artery
Blockage
Dead muscle tissue
Blockage of a coronary artery, resulting in a
heart attack

19. 23.6 CONNECTION: What is a heart attack?
Plaque
Epithelium
Atherosclerosis
Plaques develop inside inner walls of blood vessels
Plaques narrow blood vessels
Blood flow is reduced
Smooth Muscle ConnectiveTissue
Atherosclerosis: a normal artery (left) and an artery partially closed by plaque (right)

20. 23.7 The structure of blood vessels fits their functions
Capillaries
– Thin walls: a single layer of epithelial cells
– Narrow: blood cells flow in a single file
– Increase surface area for gas and fluid exchange
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Diffusion of
Molecules
Capillary
Interstitial
Fluid
Tissue cell
Diffusion
between blood
and tissue cells

21. 23.7 The structure of blood vessels fits their functions
Arteries and veins
–Lined by single layer of epithelial cells
–Smooth muscle in walls can reduce blood
flow
–Elastic fibers permit recoil after stretching
–Veins have one-way valves that restrict
backward flow
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22. Basal lamina
Epithelium
Smooth
Muscle
Connective
Tissue
Capillary
Epithelium
Epithelium
Smooth
Muscle
Valve
Connective
Tissue
Artery Vein
Arteriole Venule
Structural relationships of blood vessels

23. 23.8 Blood pressure and velocity reflect the structure and
arrangement of blood vessels
Blood pressure: The force blood exerts on vessel
walls
–Depends on cardiac output and resistance of vessels
–Decreases as blood moves away from heart
–highest in arteries lowest in veins
–It is measured as
– Systolic pressure: caused by ventricular contraction
–Diastolic pressure: low pressure between contractions
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24. SSTTRRUUCCTTUURREE
AANNDD FFUUNNCCTTIIOONN
OOFF BBLLOOOODD
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25. 23.12 Blood consists of red and white blood cells suspended in
plasma
Plasma is about 90% water
Plasma contains
– Various inorganic ions
– Proteins, nutrients
– Wastes, gases
– Hormones
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26. Plasma (55%)
Constituent
Solvent for carrying
Water other substances
Osmotic balance,
pH buffering, and
maintaining ion
concentration of
interstitial fluid
Ions (blood electrolytes)
Major functions
Sodium
Potassium
Calcium
Magnesium
Chloride
Bicarbonate
Centrifuged
blood
Sample
Plasma proteins
Osmotic balance
and pH buffering
Fibrinogen Clotting
Immunoglobulins Defense
(antibodies)
Substances transported by blood
Nutrients (e.g., glucose, fatty acids, vitamins)
Waste products of metabolism
Respiratory gases (O2 and CO2)
Hormones

27. 23.12 Blood consists of red and white blood cells
suspended in plasma
Red blood cells (erythrocytes)
– Transport O2 bound to hemoglobin
White blood cells (leukocytes)
– Function inside and outside the circulatory
system
– Fight infections and cancer
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28. Cellular elements (45%)
Centrifuged
blood
Sample
Number
Cell type Functions
per μL (mm3) of blood
Erythrocytes
(red blood cells)
5–6 million
Transport of
oxygen (and
carbon dioxide)
Leukocytes
(white blood cells) Defense and
5,000–10,000
Immunity
Basophil
Lymphocyte
Eosinophil
Neutrophil Monocyte
Platelets Blood clotting
250,000–
400,000

29. 23.13 CONNECTION: Too few or too many red blood cells can be
unhealthy
Anemia
– Abnormally low amounts of hemoglobin or red blood cells
– Causes fatigue due to lack of oxygen in tissues
Erythropoietin hormone (EPO) Regulates red blood cell
production
Some athletes artificially increase red blood cell production
by injecting erythropoietin which can lead to
Clotting
Stroke
Heart failure
Death
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30. 23.14 Blood clots plug leaks when blood vessels are injured
When a blood vveesssseell iiss ddaammaaggeedd
– Platelets help trigger the conversion of fibrinogen to
fibrin
– Which forms a clot that plugs the leak
TThhee bblloooodd-cclloottttiinngg pprroocceessss
– Platelets adhere to exposed connective tissue
– Platelets form a plug
– A fibrin clot traps blood cells
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31. 1 2
Fibrin clot
traps
blood cells
3
Platelet plug
Forms
Platelet plug
Platelets adhere
to exposed
connective tissue
Epithelium
Connective
Tissue
Platelet
The blood-clotting process
A fibrin clot

32. You should now be able to
1- Explain how geese can fly at altitudes higher than Mount Everest
2- Describe the three main phases of gas exchange in a human
3- Describe four types of respiratory surfaces and the types of animals
that use them
4- Explain how breathing air compares to using water for gas exchange
Describe the parts and functions of the human respiratory system
6- Describe the impact of smoking on human health
7- Explain how blood transports gases between the lungs and tissues of
the body
8- Describe the functions of hemoglobin
9- Explain how a fetus obtains oxygen before and after birth
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33. You should now be able to
ب ن ھذا ا
ء

34. د ا
ر
ك
1. Explain how the circulatory systems of a giraffe and snake
resist gravity
2. 2. Describe the general need for and functions of a
circulatory system
3. Compare the structures and functions of gastrovascular
cavities, open circulatory systems, and closed circulatory
systems
4. Compare the circulatory systems of a fish, frog, and mammal
5. Explain how heartbeats are controlled
6. Describe the causes and consequences of a heart attack and
cardiovascular disease
7. Relate the structure of blood vessels to their functions
8. Describe the components of blood and their functions
9. Describe the process of blood clotting
10. Describe the causes and treatments for leukemia
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35. Circulation و
د دورة ا ا
ـــــــــــــــــــــــــــــــــ ا ــــــــــ ا

36. آ
ت ا Mechanisms Of Internal Transport ا اNutrients اد ا
Gas Exchange دل ا ! #
زات Removal Of ا
ا تWastes $% ' ()* Diffusion ,*-. ا ر/
Inadequate For Large And Complex

37. #2 م ا 456 #47 89 :4
ة وا ةBodies
An Internal Transport System Assists
Diffusion By Moving Materials Between
اد ا 7 ر ,*-. ا / ا ا ز ا ;5 /4
'7 ;2

38. و
Surfaces Of The Body =4 ا ?
Internal Tissues ا ا 4-@ ا
Gastrovascular Cavity / ي ا
ا
* ا
Cnidarians And Flatworms ان وا ار ? #
C 8
Digestion =%; ا / 8
Distribution Of Substances اد ا D ز و
Circulatory System وري ز ا ; ن ا 2*

39. Circulation و
د دورة ا ا
ـــــــــــــــــــــــــــــــــ ا ــــــــــ ا

40. ا
وBlood Vessels / ا @ ا
ة ا ور ا Open Circulatory Systems E* F;5@ Arthropods 5 ت ا @
را
Molluscs