1. The Cardiovascular System: The Blood
Chapter 19
The Cardiovascular System: The Blood

2. What is blood?
Blood is a connective tissue composed of a liquid extracellular matrix called plasma. It has cells and cell fragments dissolved in it.
The cardiovascular system is made up of blood, the heart, and blood vessels.
Principles of Human Anatomy and Physiology, 11e

3. Functions of Blood Transportation
O2, CO2, metabolic wastes, nutrients, heat & hormones
Regulation
helps regulate pH through buffers
helps regulate body temperature
helps regulate water content of cells
Protection from disease & loss of blood
Hematology is study of blood and blood disorders
Principles of Human Anatomy and Physiology, 11e

4. Physical Characteristics of Blood
Thicker than water and therefore flows more slowly than water
Feels sticky
Temperature of degrees F
pH 7.4 ( )
8 % of total body weight
Blood volume
5 to 6 liters in average male
4 to 5 liters in average female
Principles of Human Anatomy and Physiology, 11e

5. Techniques of Blood Sampling
Venipuncture
Most common method
sample taken from vein with hypodermic needle & syringe
Finger or heel stick
Used by diabetics to monitor blood sugar
Used to test blood of infants
Arterial stick: used to determine oxygen levels
Principles of Human Anatomy and Physiology, 11e

6. COMPONENTS OF BLOOD Blood consists of 55% plasma and 45% of cells.
Blood plasma consists of 91.5% water and 8.5% solutes.
Principal solutes include nutrients, enzymes, hormones, respiratory gases, electrolytes, and waste products.
Principles of Human Anatomy and Physiology, 11e

7. Blood Cells Red blood cells, 40% ( erythrocytes )
White blood cells, 20% ( leukocytes )
neutrophils, eosinophils, basophils
lymphocytes = T cells, B cells, and natural killer cells
monocytes
Platelets, 30% (special cell fragments)
Principles of Human Anatomy and Physiology, 11e

8. Hematocrit
Hematocrit is the percentage of total blood volume occupied by RBCs.
Anemia
not enough RBCs or not enough hemoglobin
Can be due to leukemia, iron deficiency, or B12 deficiency
Vitamins or injections of iron can treat anemia
Polycythemia
too many RBCs (over 65%)
dehydration, blood loss (including menstruation), blood doping in athletes (common in professional cycling to increase O2 supplies to the blood, muscles, and lungs)

9. Formation of Blood Cells
Most blood cells types need to be continually replaced
die within hours, days or weeks
process of blood cells formation is hematopoiesis or hemopoiesis
In the embryo
occurs in yolk sac, liver, spleen, thymus, lymph nodes & red bone marrow
In adults
occurs only in red marrow of flat bones like sternum, ribs, skull & pelvis and ends of long bones
Principles of Human Anatomy and Physiology, 11e

10. Red Blood Cells or Erythrocytes
Contain oxygen-carrying protein hemoglobin that gives blood its red color
1/3 of cell’s weight is hemoglobin
Biconcave disk 8 microns in diameter
increased surface area/volume ratio
flexible shape for narrow passages
no nucleus or other organelles
Principles of Human Anatomy and Physiology, 11e

11. RBC Life Cycle RBCs live only 120 days
wear out from bending to fit through capillaries
no repair possible due to lack of organelles
Worn out cells removed by macrophages in spleen & liver
Principles of Human Anatomy and Physiology, 11e

12. Erythropoiesis: Production of RBCs
Erythrocyte formation, called erythropoiesis, occurs in adult red bone marrow of certain bones.
It takes 1-2 days for a mature red blood cell to be formed and released into the blood stream.
Principles of Human Anatomy and Physiology, 11e

13. Hemoglobin Each RBC has 280 million hemoglobin molecules
Each one can bind 4 molecules of oxygen (to the iron at the center of the molecule).
Hemoglobin removes CO2 from the blood
Hemoglobin also regulates blood pressure by regulating nitric oxide in the blood
Principles of Human Anatomy and Physiology, 11e

14. WHITE BLOOD CELLS
Leukocytes (WBCs) have a nucleus but do not have hemoglobin.
Granular leukocytes include eosinophils, basophils, and neutrophils based on the straining of the granules.
Agranular leukocytes do not have cytoplasmic granules and include the lymphocytes and monocytes.
Principles of Human Anatomy and Physiology, 11e

15. WBC Physiology Less numerous than RBCs
5000 to 10,000 cells per drop of blood
1 WBC for every 700 RBC
Leukocytosis is a high white blood cell count
microbes, disease, strenuous exercise, anesthesia, cancer or surgery
Leukopenia is low white blood cell count
radiation, shock or chemotherapy
Only 2% of total WBC population is in circulating blood at any given time
rest is in lymphatic fluid, skin, lungs, lymph nodes & spleen
Principles of Human Anatomy and Physiology, 11e

16. Neutrophils (Granulocyte)
The most abundant WBC
60 to 70% of circulating WBCs
First cells to migrate to the site of bacterial infection or cancer formation.
Also involved in healing injuries
release lysozymes which destroy/digest bacteria
release defensin proteins that act like antibiotics & poke holes in bacterial cell walls destroying them
release strong oxidants (bleach-like, strong chemicals) that destroy bacteria
Principles of Human Anatomy and Physiology, 11e

17. Eosinophils (Granulocyte)
2 to 4% of circulating WBCs
Combat parasites and infections
Fight allergies and asthma
Principles of Human Anatomy and Physiology, 11e

18. Basophils (Granulocyte)
Less than 1% of circulating WBCs
Store histamine and can contribute to allergic reactions
Also contain heparin, which prevents blood from clotting too quickly
Principles of Human Anatomy and Physiology, 11e

19. Lymphocyte (Agranulocyte)
20 to 25% of circulating WBCs
The main soldiers in the immune system battles
B cells
destroy bacteria and their toxins
turn into plasma cells that produces antibodies
T cells
attack viruses, fungi, transplanted organs, cancer cells & some bacteria
Natural killer cells (NKC)
attack many different microbes & some tumor cells
destroy foreign invaders by direct attack
Principles of Human Anatomy and Physiology, 11e

20. Monocyte (Agranulocyte)
3 to 8% of circulating WBCs
Stored in the spleen
Produce macrophages which attack bacteria
Destroy microbes and clean up dead tissue following an infection
Principles of Human Anatomy and Physiology, 11e

21. PLATELETS
Platelets help stop blood loss from damaged vessels by forming a platelet plug.
Their granules also contain chemicals that promote blood clotting.
Principles of Human Anatomy and Physiology, 11e

22. Platelet (Thrombocyte) Anatomy
Disc-shaped cell fragment with no nucleus
They are produced in the bone marrow and live 5 to 9 days in the blood stream before being recycled by the spleen and liver.
Principles of Human Anatomy and Physiology, 11e

23. Bone Marrow Transplant
Bone marrow transplant replaces diseased marrow with healthy marrow.
Patient’s diseased marrow is destroyed by cancer or disease.
Healthy marrow is supplied by a donor or the patient. It is removed (painfully) by sticking a needle into the hipbone.
Risks to recipient include:
Infection due to decreased WBC
T cells might attack new bone marrow
Must take immunosuppressant drugs for life
Principles of Human Anatomy and Physiology, 11e

24. Cord-Blood Transplant
Stem cells are taken from the umbilical cord and frozen
This method offers several advantages over marrow transplant.
Easy to obtain
More abundant
Are not rejected by patient
Don’t transmit infections
Can be stored, frozen, forever
Principles of Human Anatomy and Physiology, 11e

25. Hemostasis
Stoppage of bleeding in a quick & localized fashion when blood vessels are damaged
Prevents hemorrhage (loss of a large amount of blood)
Methods utilized
vascular spasm
platelet plug formation
blood clotting
Principles of Human Anatomy and Physiology, 11e

26. Vascular Spasm
Damage to blood vessel produces stimulates pain receptors
Small blood vessels are contracted which reduces blood flow to the injury site

27. Platelet Plug Formation
Steps in the process
(1) platelet adhesion (2) platelet release reaction (3) platelet aggregation
Principles of Human Anatomy and Physiology, 11e

28. Platelet Adhesion
Platelets stick to exposed collagen underlying damaged cells in vessel wall
Principles of Human Anatomy and Physiology, 11e

29. Platelet Release Reaction
Platelets activated by adhesion
Extend projections to make contact with each other
This decreases blood flow to injury site
Principles of Human Anatomy and Physiology, 11e

30. Platelet Aggregation
Activated platelets stick together and activate new platelets to form a mass called a platelet plug
Plug reinforced by fibrin threads formed during clotting process
Principles of Human Anatomy and Physiology, 11e

31. Clot Retraction & Blood Vessel Repair
The plug stops the bleeding, then…
Edges of damaged vessel are pulled together
Fibroblasts & endothelial cells repair the blood vessel
Principles of Human Anatomy and Physiology, 11e

32. Blood Clotting Blood drawn from the body thickens into a gel
gel separates into liquid (serum) and a clot of insoluble fibers (fibrin) in which the cells are trapped
If clotting occurs inside the body, it is called a thrombosis
Having vitamin K in your diet can help prevent blood clotting
Principles of Human Anatomy and Physiology, 11e

33. Blood Groups and Blood Types
RBC surfaces are marked by antigens, which determine blood type
Principles of Human Anatomy and Physiology, 11e

34. ABO Blood Groups Blood types in humans are:
display only antigen A -- blood type A
display only antigen B -- blood type B
display both antigens A & B -- blood type AB
display neither antigen -- blood type O
Type O is the universal donor
Type AB is the universal receiver
Principles of Human Anatomy and Physiology, 11e

35. RH blood groups Antigen was discovered in blood of Rhesus monkey
People with Rh agglutinogens on RBC surface are Rh+.
Most people are Rh +
If an Rh - woman is pregnant and the baby is Rh+, the mother’s body may reject the pregnancy; she must take anti-rejection drugs and be closely monitored.
Principles of Human Anatomy and Physiology, 11e

36. DISORDERS: HOMEOSTATIC IMBALANCES
Anemia
Sickle-cell
Hemophilia
Disseminated intravascular clotting
Acute leukemia
chronic leukemia
Principles of Human Anatomy and Physiology, 11e

37. Anemia = Not Enough RBCs
Symptoms
oxygen-carrying capacity of blood is reduced
fatigue, cold intolerance & paleness
Types of anemia
iron-deficiency =lack of absorption or loss of iron
pernicious = lack of intrinsic factor for B12 absorption
hemorrhagic = loss of RBCs due to bleeding (ulcer)
hemolytic = defects in cell membranes cause rupture
thalassemia = hereditary deficiency of hemoglobin
aplastic = destruction of bone marrow (radiation/toxins)
Principles of Human Anatomy and Physiology, 11e

38. Sickle-cell Anemia Genetic defect in hemoglobin molecule
RBC is deformed
sickle-shaped cells rupture easily = causing anemia & clots
Found among populations in malaria belt
Mediterranean Europe, sub-Saharan Africa & Asia
Principles of Human Anatomy and Physiology, 11e

39. Hemophilia Inherited deficiency of clotting factors
bleeding spontaneously or after minor trauma
subcutaneous & intramuscular hemorrhaging
nosebleeds, blood in urine, articular bleeding & pain
Treatment is transfusions of fresh plasma or concentrates of the missing clotting factor
Principles of Human Anatomy and Physiology, 11e

40. Disseminated Intravascular Clotting
Life threatening paradoxical presence of blood clotting and bleeding at the same time throughout the whole body
Associated with infections, hypoxia, low blood flow rates, trauma, hypotension & hemolysis
Clots cause necrosis leading to multisystem organ failure

41. Leukemia Acute leukemia uncontrolled production of immature leukocytes
crowding out of normal red bone marrow cells by production of immature WBC
prevents production of RBC & platelets
Chronic leukemia
accumulation of mature WBC in bloodstream because they do not die
Principles of Human Anatomy and Physiology, 11e