1. Chapters 10 & 11 Blood and Cardiovascular System
Course of Study:
9.) Identify structures and functions of the cardiovascular system.
• Tracing the flow of blood through the body
• Identifying components of blood
• Describing blood cell formation
• Distinguishing among human blood groups
• Describing common cardiovascular diseases and disorders
Examples: myocardial infarction, mitral valve prolapse, varicose veins, arteriosclerosis

2. Components of Blood

3. Blood The only fluid tissue in the human body
Classified as a connective tissue
Living cells = formed elements
Non-living matrix = plasma

4. Components of Blood:
Although blood appears to be a thick, homogenous liquid, the microscope reveals it has both solid and liquid components
Blood is a complex connective tissue (it is the only liquid tissue) in which living blood cells, the formed elements, are suspended in a nonliving fluid matrix called plasma.

5. Components of Blood: The heavier formed elements are packed down
Blood in a centrifuge:
The heavier formed elements are packed down
The plasma rises to the top
Most of the reddish mass at the bottom of the tube consists of erythrocytes, the red blood cells that function in oxygen transport
Although, it is barely visible in there is a thin, whitish layer called the “buffy coat” at the junction between the formed elements and the plasma. This layer contains leukocytes (leuko=white), the white blood cells that act in various ways to protect the body, and platelets, cell fragments that function in the blood clotting process.
Erythrocytes normally account for about 45% of the total volume of a blood samples, a percentage known as a “hematocrit”.
White blood cells and platelets contribute less than 1%.
Plasma makes up most of the remaining 55% of whole blood.

6. Figure 10.1 in your book, pg.329

7. Physical Characteristics and Volume
Blood is a sticky opaque fluid with a characteristic metallic taste
Depending on the amount of oxygen it is carrying, the color of blood varies from scarlet (oxygen-rich) to a dull red (oxygen- poor)
Blood is heavier than water and about five times thicker, or more viscous, largely because of its formed elements.
Blood is slightly alkaline (basic) with a pH between 7.35 and 7.45.
Its temperature is always slightly higher than body temperature (38°C or 100.4°F)
Blood accounts for approximately 8% of body weight, and its volume in healthy males is 5-6 liters, or approximately 6 quarts…so what is it in women? (2 point bonus…)

8. Plasma Is approximately 90% water Is the liquid part of the blood
Over 100 different substances are dissolved in this straw- colored fluid such as nutrients, salts (electrolytes), respiratory gases, hormones, plasma proteins, and various wastes and products of cell metabolism
The composition of plasma varies as cells remove or add substances to the blood…assuming a healthy diet, however, the composition is kept relatively constant by various homeostatic mechanisms of the body

9. Plasma Proteins The most abundant solutes in plasma
Except for antibodies and protein-based hormones, most plasma proteins are made by the liver.
Serve a variety of functions
Albumin: contributes to osmotic pressure of blood, which acts to keep water in the bloodstream
Clotting Proteins: Help stem blood loss when a blood vessel is injured
Antibodies: Help protect the body from pathogens (disease causing organisms)
Plasma proteins are NOT taken up by cells to be used as food fuels or metabolic nutrients, as are other solutes such as glucose, fatty acids, and oxygen.

10. Formed Elements Erythrocytes Leukocytes Platelets
If you observe a stained smear of human blood under a microscope, you will see smooth, disc-shaped red blood cells, a variety of gaudily stained white blood cells, and most likely, some scattered platelets that look like debris.
Erythrocytes vastly outnumber the other types of formed elements.

11. Erythrocytes: “red blood cells” (RBCs)
Salmon-colored, biconcave disks
Function to ferry oxygen in blood to all cells of the body
RBCs differ from other blood cells because they are anucleate meaning they lack a nucleus and they also contain very few organelles (which also means they cannot divide)
Mature RBCs are literally sacs of hemoglobin molecules
Hemoglobin: iron-bearing protein, transports the bulk of the oxygen that is carried in the blood
In fact, because erythrocytes lack mitochondria and make ATP by anaerobic mechanisms, they do not use up any of the oxygen they transport, making them very efficient oxygen transporters indeed!
RBCs live about 120 days and are then phagocytized by the liver and spleen

12. Anemia & Sickle-Cell Anemia
Anemia: Decrease in the oxygen-carrying ability of the blood
May be result of: 1) Lower than normal number of RBCs 2) abnormal or deficient hemoglobin content in the RBCs or
Sickle-Cell Anemia (SCA):
The abnormal hemoglobin formed becomes spiky and sharp when the RBCs unload oxygen molecules or when the oxygen content of the blood is lower than normal (like during exercise, anxiety, or other stressful situations).
The deformed (crescent-shaped) erythrocytes rupture easily and dam up in small blood vessels. These events interfere with oxygen delivery and cause extreme pain.
It is amazing that this havoc results from a change in just ONE of the amino acids in each of the beta chains of the globin molecule!
SCA occurs chiefly in black people who live in the malaria belt of Africa and among their descendants….Apparently, the same gene that causes sickling makes RBCs infected by the malaria-causing parasite stick to the capillary walls and then lose potassium, an essential nutrient for survival of the parasite…Hence, the malaria- causing parasite is prevented from multiplying within the RBCs, and individuals with the sickle gene have a better chance of surviving where malaria is prevalent!!! Cool.

13. Leukocytes: “white blood cells” (WBCs)
Far less numerous than RBCs
Are crucial to body defense against disease
Include: Granulocytes (neutrophils, eosinophils, basophils) & Agranulocytes (lymphocytes, monocytes)
WBCs are the only complete cells in the blood; that is, they contain nuclei and the usual organelles
WBCs form a protective, movable army that helps defend the body against damage by bacteria, viruses, parasites, and tumor cells….so they have special characteristics…

14. More About Leukocytes (WBCs)…
RBCs are confined to the bloodstream and carry out their function in the blood…not WBCs…
WBCs are able to slip into and out of the blood vessels - a process called diapedesis.
The circulatory system is simply their means of transportation to areas of the body where their services are needed for inflammatory or immune responses (we will look more at this in ch.12)
WBCs can also locate areas of tissue damage and infection in the body by responding to certain chemicals that diffuse from the damaged cells (they “pick up the scent” and move there…pretty neat!) They pinpoint areas of tissue damage and rally round in large numbers to destroy microorganisms or dead cells.
Whenever WBCs mobilize for action, the body speeds up their production, and as many as twice the normal number of WBCs may appear in the blood within a few hours. A total WBC count above 11,000 cells/mm3 is referred to as leukocytosis….this generally indicates that a bacterial or viral infection is stewing in the body. Leukopenia, the opposite condition, is an abnormally low WBC count. It is commonly caused by certain drugs, such as corticosteroids and anticancer agents.

15. Leukocytosis & Leukemia
Leukocytosis: Normal and desirable response to infectious threats to the body.
By contrast, the excessive production of abnormal WBCs that occurs in infectious mononucleosis and leukemia is distinctly pathological.
Leukemia:
Literally “white blood”
The bone marrow becomes cancerous, and huge numbers of WBCs are turned out rapidly
Seems like not a bad thing….but….the “newborn” WBCs are immature and incapable of carrying out their normal protective functions. So, the body becomes the easy prey of disease-causing bacteria and viruses.

16. 2 Major Groups of WBCs: Granulocytes Granule containing Agranulocytes
Lack visible granules
Neutrophils
Avid phagocytes at sites of acute infection
Eosinophils
Their number increases rapidly during allergies and infections by parasitic worms (like tapeworm)
Basophils
Rarest of WBCs that contain large histamine-containing granules
Histamine is an inflammatory chemical that makes blood vessels leaky and attracts other WBCs to the inflammatory site.
Lymphocytes
Take up residence in lymphatic tissues, where they play an important role in the immune response
Monocytes
Largest of all WBCs
They migrate into tissues, change into macrophages with huge appetites. Macrophages are very important in fighting chronic infections, such as tuberculosis

17. Platelets
Really aren’t cells…they are fragments of bizarre multinucleate cells called megakaryocytes which pinch off thousands of anucleate platelet “pieces” that quickly seal themselves off from the surrounding fluids
Platelets appear as darkly staining, irregularly shaped bodies scattered among the other blood cells
The normal platelet count in blood is about 300,000/mm3.
Platelets are needed for the clotting process that occurs in plasma when blood vessels are ruptured or broken

18. Hemostasis (hem=blood; stasis=standing still)
The process of stopping bleeding
Coagulation causes the formation of a blood clot
3 Key Events:
1. Blood vessel spasm - damaged or broken vessels stimulate muscle tissue in the walls of the blood vessels to contract. This slows or stops blood flow, lasts for several minutes. Also, platelets release serotonin, a vasoconstrictor which maintains the muscle spasm even longer.
2. Platelet plug formation - platelets stick to surfaces of damaged blood vessels and to each other to form a "plug"
3. Blood coagulation - most effective, forms a blood clot (hematoma). Injury causes an increase in the release of coagulants. Main event - conversion of fibrinogen into long protein threads called fibrin.
Blood clotting - Animation - YouTube

19. Undesirable Clotting:
Sometimes clots form in intact blood vessels, particularly in the legs
A clot that develops and persists in an unbroken blood vessel is called a thrombus
If large enough, it may prevent blood flow to the cells beyond the blockage…for example…if a thrombus forms in the blood vessels serving the hearth (coronary thrombosis), the consequences may be death of heart muscle and a fatal heart attack
If a thrombus breaks away from the vessel wall and floats freely in the bloodstream, it becomes an embolus. An embolus is usually no problem unless or until it lodges in a blood vessel too narrow for it to pass through…for example…a cerebral embolus may cause a stroke
A number of anticoagulants, most importantly aspirin, heparin, and dicumarol, are used clinically for thrombus-prone patients

20. Cool Picture from your Text… Reads: Fibrin Clot
Cool Picture from your Text… Reads: Fibrin Clot. Scanning electron micrograph of red blood cells trapped in a mesh of fibrin threads.

21. Blood Cell Formation (Hematopoiesis)

22. Blood Cell Formation Occurs in red bone marrow
In adults, this tissue is found is found chiefly in the flat bones of the skull and pelvis, the ribs, sternum, and proximal epiphyses of the humerus and femur
Each type of blood cell is produced in different numbers in response to changing body needs and different stimuli…after they mature, they are discharged into the blood vessels surrounding the area.
All formed elements arise from a common type of stem cell: the hemocytoblast, which resides in the red bone marrow

23. Erythrocyte Development:
Because RBCs are anucleate (have no nucleus) they are unable to synthesize proteins, grow, or divide
As they age, RBCs become more rigid and begin to fragment, or fall apart, in days. Their remains are eliminated by phagocytes in the spleen or liver.
Lost cells are replaced by the division of hemocytoblasts in the red bone marrow.
The developing RBCs divide many times and then begin synthesizing huge amounts of hemoglobin…suddenly when enough hemoglobin has been accumulated, the nucleus and most organelles are ejected and the cell collapses inward.
The result is the young RBC, called a reticulocyte because it still contains some rough endoplasmic reticulum (ER)
The reticulocytes enter the bloodstream to begin their task of transporting oxygen….within 2 days of release, they have ejected the remaining ER and have become fully functioning erythrocytes.
The entire developmental process from hemocytoblast to mature RBC takes 3-5 days.

24. Erythrocyte Development:
Rate of production is controlled by a hormone (not so surprisingly!) called erythropoietin
Normally a small amount of erythropoietin circulates in the blood at all times, and the red blood cells are formed at a fairly constant rate
Although the liver produces some, the kidneys play the major role in producing this hormone.
When blood levels of oxygen begin to decline for any reason, the kidneys step up their release of erythropoietin…the erythropoietin targets the bone marrow, prodding it into “high gear” to turn out more RBCs.
As you might expect, and overabundance of erythrocytes, or an excessive amount of oxygen in the bloodstream, decreases erythropoietin release and red blood cell production.

25. Leukocyte and Platelet Development
Also stimulated by hormones like erythrocytes
These “colony stimulating factors (CSFs)” and “interleukins” not only prompt red bond marrow to turn out leukocytes, but also marshal up an army of WBCs to ward off attacks by enhancing the ability of mature leukocytes to protect the body
They are released in response to specific chemical signals in the environment such as inflammatory chemicals and certain bacteria or their toxins
The hormone “thrombopoietin” accelerates the production of platelets, but little is known about how that process is regulated

26. Human Blood Groups

27. Antigens
Blood transfusions can save lives, but people have different blood groups, and transfusing incompatible or mismatched blood can be fatal
The plasma membranes of RBCs, like those of all body cells have genetically determined proteins (antigens), which identify each person as unique!
An antigen is a substance that the body recognizes as foreign; it stimulates the immune system to release antibodies or use other means to mount a defense against it

28. Antigens & Antibodies
Most antigens are foreign proteins like viruses or bacteria that have managed to invade the body
Each of us tolerates our own cellular (self) antigens, but one person’s RBC proteins will be recognized as foreign if transfused into another person with different RBC antigens
The “recognizers” are antibodies present in the plasma that attach to RBCs bearing surface antigens different form those on the patient’s RBCs

29. Antibodies and Agglutination
At this point of recognition of foreigner…binding of antibodies causes the RBCs to clump, called agglutination
This leads to clogging of small blood vessels throughout the body
During the next few hours, the foreign RBCs are ruptured and the hemoglobin is released into the blood stream
Although the transfused blood is unable to deliver the increased oxygen-carrying capacity hoped for and some tissue areas may be deprived of blood….the most devastating consequence…

30. Negative Consequences of Transfusion of Mismatched Blood
The most devastating consequence of severe transfusion reactions is that the freed hemoglobins block the kidney tubules and cause kidney failure
Transfusion reactions can also cause fever, chills, nausea, and vomiting, but in the absence of kidney shutdown these reactions are rarely fatal
Treatment is aimed at preventing kidney damage by infusing alkaline fluids to dilute and dissolve the hemoglobin and diuretics to flush it out of the body in urine

31. ABO and Rh Grouping
There are over 30 common RBC antigens in humans, allowing each person’s blood cells to be classified into different blood groups
However, it is the antigens of the ABO and Rh blood groups that cause the most vigorous transfusion reactions

32. ABO Blood Groups
Based on which of two antigens, type A or type B, a person inherits
Absence of both antigens results in type O blood
Presence of both antigens leads to type AB
Possession of type A gives type A blood and possession of type B gives type B blood
In the ABO blood group, antibodies are formed during infancy against the ABO antigens not present on your own RBCs
For example: a baby with neither the A nor the B antigen (O) forms both anti-A and anti-B antibodies, while those with type A antigens (A) form anti-B antibodies

33. Summary of ABO (from your text, pg.340)
*Just remember, the antigens on the surface of your cells (or donated cells) will cause a reaction if your immune system does not recognize them as being part of you. Hence, if you are Type A, and transfused with Type B, your body will mobilize a massive immune response against the "invading" blood. This will cause coagulation of blood and death.

34. Rh blood groups
Named because 1 of the 8 Rh antigens was originally identified in Rhesus monkeys!
Later the same antigen was discovered in human beings
Most Americans are Rh+, meaning that their RBCs carry the Rh antigen…if you are negative, then you do not carry the Rh antigen
Unlike the antibodies of the ABO system, anti-Rh antibodies are not automatically formed and present in the blood of Rh- people.
However, if an Rh- person receives mismatched blood (Rh+), shortly after the transfusion his or her immune system becomes sensitized and begins producing antibodies (anti-Rh+) against he foreign blood type.
Hemolysis (rupturing of the RBCs) does not occur with the first transfusion because it takes time for the body to react and start making antibodies…however, the second time and every time after, a typical transfusion reaction occurs in which the patient’s antibodies attack and rupture the donor’s Rh+ RBCs

35. Important Rh Related Problem
Occurs in pregnant Rh- women that are carrying Rh+ babies
The first pregnancy usually results in the delivery of a healthy baby…but because the mother is sensitized by Rh+ antigens that have passed through the placenta into her bloodstream, she will form anti-Rh+ antibodies…
Unless she is treated with RhoGAM shortly after giving birth..RhoGAM is an immune serum that prevents this sensitization…
If she is not treated and becomes pregnant again with an Rh+ baby, her antibodies will cross through the placenta and destroy the baby’s RBCs, producing a condition known as “hemolytic disease of the newborn”.
The baby is anemic and becomes hypoxic (deficiency of oxygen) and cyanotic (the skin takes on a blue cast). Brain damage and even death may result unless fetal transfusions are done before birth to provide more RBCs for oxygen transport.

36. Blood Typing
The importance of determining the blood group of both the donor and the recipient BEFORE blood is transfused is glaringly obvious!
Essentially in blood typing, it involves testing the blood by mixing it with 2 different types of immune serum: anti-A and anti- B….Agglutination occurs when RBCs of a group A person are mixed with the anti-A serum, but not when they are mixed with the anti-B serum (& vise versa)
Because it is critical that blood groups be compatible, cross matching is also done….involves testing for agglutination of donor RBCs by the recipient’s serum and of the recipient's RBCs by the donor serum
Typing for Rh factors is done in the same manner as ABO blood typing

37. Blood Typing
From your text….
Page 341

38. Monday Heart Dissection!
Today: 1. Heart Labeling Quiz 2. Complete PP Notes 3. Disorders with Nooks
Monday Heart Dissection!
Remember:

39. Tracing the Flow of Blood through the Body (Chapter 11)
Looking specifically at the heart, veins, and arteries

40. The Cardiovascular System
A closed system of the heart and blood vessels
The heart pumps blood
Blood vessels allow blood to circulate to all parts of the body
The function of the cardiovascular system is to deliver oxygen and nutrients and to remove carbon dioxide and other waste products

41. The Heart Location About the size of your fist
Thorax between the lungs
Pointed apex directed toward left hip
About the size of your fist

42. The Heart: Coverings
Pericardium – a double serous membrane that covers the heart like a bag, but has two layers with fluid in between…
Visceral pericardium
Next to heart
Parietal pericardium
Outside layer
Serous fluid fills the space between the layers of pericardium- reduces friction!

43. The Heart: Heart Wall Three layers Epicardium Myocardium Endocardium
Outside layer
This layer is the parietal pericardium
Connective tissue layer
Myocardium
Middle layer
Mostly cardiac muscle
Endocardium
Inner layer
Endothelium

44. Physiology of the Heart
As the heart beats or contracts, the blood makes continuous round trips-into and out of the heart, through the rest of the body, and then back to the heart-only to be sent out again
The amount of work that a heart does is almost too incredible to believe…
In one day it pushes the body’s supply of 6 quarts or so of blood (6Liters) through the blood vessels over 1,000 times!
Meaning that it actually pumps about 6,000 quarts (or liters) of blood every single day!

45. Blood Circulation
The systemic (to the body) and pulmonary (to the lungs) circuits are shown here
The left side of the heart is the systemic pump…supplies oxygen & nutrient rich blood to all body organs
The right side of the heart is the pulmonary circuit pump…receives relatively oxygen poor blood from the veins of the body and pumps it out to the lungs where oxygen is picked up and carbon dioxide is unloaded
Figure 11.3

46. Path of Blood Through the Heart Quick Overview Give Handout!
1. Deoxygenated blood enters right atrium through the vena cava 2. Blood moves into the right ventricle 3. Blood goes out the pulmonary arteries and heads to the lungs 4. Blood returns from the lungs and enters the left atrium 5. Blood moves into the left ventricle 6. Oxygenated blood moves out of the left ventricle through the aorta and to the body

47. The Heart: Valves Allow blood to flow in only one direction
Valves open as blood is pumped through
Held in place by chordae tendineae (“heart strings”)
Close to prevent backflow

48. The Heart: Valves Four valves
Atrioventricular valves – between atria and ventricles
Bicuspid valve (left)
Tricuspid valve (right)
Semilunar valves between ventricle and artery
Pulmonary semilunar valve
Aortic semilunar valve

49. Sounds of the Heart
When using a stethoscope, you can hear two distinct sounds during each cardiac cycle
These heart sounds are often described by the two syllables “lub” and “dup”, and the sequence is lub-dup, pause, lub-dup, pause, etc…
The first sound “lub” is caused by the closing of the AV valves
The second sound “dup” is caused by the closing of the semilunar valves at the end of systole

50. The Heart: Associated Great Vessels
Aorta
Leaves left ventricle
Large vessel that delivers blood to the body
Pulmonary arteries
Leave right ventricle
Large vessel that splits into the left and right pulmonary arteries, these are the only arteries that carry deoxygenated blood
Vena cava
Enters right atrium
Superior Vena Cava - vessel the returns blood to the heart from the upper body
Inferior Vena Cava - vessel the returns blood to the heart from the lower body
Pulmonary veins (four)
Enter left atrium
Pulmonary Veins - returns oxygenated blood from the lungs

51. The Heart: Cardiac Cycle
Atria contract simultaneously
Atria relax, then ventricles contract
Systole = contraction
Diastole = relaxation

52. The Heart: Regulation of Heart Rate
Increased heart rate
Sympathetic nervous system
Crisis
Low blood pressure
Hormones
Epinephrine
Thyroxine
Exercise
Decreased blood volume
Decreased heart rate
Parasympathetic nervous system
High blood pressure or blood volume
Decreased venous return

53. Blood Vessels: The Vascular System
Taking blood to the tissues and back
Arteries and Arterioles
Carry blood Away from the heart (arterioles are just smaller arteries)
Capillaries
Are only one cell layer thick…allows easy exchanges between the blood and tissue cells
Veins and Venules
Carry blood To the heart (venules are just smaller arteries)

54. Differences Between Blood Vessel Types
Walls of arteries are the thickest
This is because arteries are much closer to the heart and must be able to expand as blood is forced into them…their walls must be strong and stretchy enough to take these extreme changes in pressure
Arterial blood is pumped by the heart
Lumens (opening in middle) of veins are larger
Veins are far from the heart in the circulatory pathway and the pressure tends to be low all of the time, so veins have thinner walls
Since the blood pressure is usually too low to force blood back to the heart…veins are modified to ensure that the amount of blood returning to the heart equals the amount being pumped out of the heart at any time…
1) The larger veins even have valves that prevent backflow of blood
2) Skeletal muscle activity enhances venous return (“milks the blood back to the heart)
3) Finally, when we inhale, the drop in pressure that occurs in the thorax causes the large veins near the heart to expand and fill helping return blood to the heart.

55. The Vascular System

56. Capillary Beds Capillary beds consist of two types of vessels
Vascular shunt
Directly connects an arteriole to a venule
True capillaries
exchange vessels, usually branch off the proximal end of the shunt and return to the distal end
Oxygen and nutrients cross to cells
Carbon dioxide and metabolic waste products cross into blood
Sphincters act as a valve to regulate the flow of blood into the capillary.

57. Pulse Pulse – pressure wave of blood
Monitored at “pressure points” where pulse is easily palpated
Figure 11.16

58. Blood Pressure
Measurements by health professionals are made on the pressure in large arteries
Systolic – pressure at the peak of ventricular contraction
Diastolic – pressure when ventricles relax
Pressure in blood vessels decreases as the distance away from the heart increases

59. Systolic pressure / diastolic pressure
Systolic occurs when blood is forced out of the left ventricle, and the aortic valve OPENS...this is the high number on a blood pressure reading
Diastolic occurs when the aortic valve closes and the ventricle relaxes, this is the lower number of the blood pressure reading.
Average (Normal) Blood Pressure = 120/80 & Average heart rate = 72 bpm
The device used to measure blood pressure is a SPHYGMOMANOMETER

60. Developmental Aspects of the Cardiovascular System
A simple “tube heart” develops in the embryo and pumps by the fourth week
The heart becomes a four-chambered organ by the end of seven weeks
Few structural changes occur after the seventh week

61. Disorders/Diseases Associated with the Cardiovascular System
Myocardial infarction
Mitral valve prolapse
Varicose veins
Artherosclerosis/Arteriosclerosis
Chronic hypertension
Murmurs
Hemophilia
Thrombocytopenia
*Include a 1 Paragraph Summary of your assigned disorder/disease with your Homework!

62. Write the Flow of Blood through the Heart, Lungs and Body!
WITHOUT
LOOKING!!
do the best you can….

63. Today’s Plans *Remember we are learning about tracing the flow of blood through the body!
1. Heart Walk Through Practice (Quiz Tomorrow!) 2. Review Assignment from Book (on the board) Due at the End of Class! 3. Tomorrow we will be taking the Heart Walk- Through Quiz and also Reviewing for your Ch.10& 11 TEST on Thursday!

65. Today’s Plans Review for Ch.10&11 Blood and Cardiovascular Test
You will work with a partner using a study guide handout to highlight/mark your notes on what to study
You will not be able to take the study guide handout out of the room
Once you have marked your notes, begin reviewing for your test tomorrow!
Heart Walk-Through Quiz
I will draw names from the hat to see what order we will go in
This quiz will be given in the hallway
When you hear your name report to the hall!