1. Bell Work How would you describe blood?
Does lower or higher density materials float?
What does proximal mean?
Where is the epiphysis of the femur located?
What is a clot?
What is blood plasma?

2. Blood The only fluid tissue in our body
It transports everything that is needed in our bodies
It has formed elements (living blood cells) and plasma (nonliving fluid matrix)

3. Hematopoiesis Blood Cell Formation
Occurs in the Red Bone Marrow or myeloid found chiefly in the flat bones of the skull and pelvis, the ribs, sternum, and the proximal epiphyses of the humerus and femur.
All blood cells arise from a common type of stem cell called the hemocytoblast, but triggers will cause the stem cells to irreversibly change to produce the different types of blood cells

4. Figure 10.4 from page 335

5. Separating Blood
Blood can be separated using a centrifuge, which uses a fast rotational motion to separate components based on densities.
Materials with high densities would sink to the bottom while lower densities would remain at the top.

6. At the top, you would have…
Plasma, which is composed of
Mostly water (90%)
Salts
Plama Proteins
Nutrients
Waste
Respiratory Gases
Hormones

7. At the bottom, you would have…
Erythrocytes

8. Erythrocytes Red blood cells
Outnumber other parts by roughly 1000 to 1
Transport oxygen and carbon dioxide
They do not have a nucleus and have very few organelles
Basically, they are a sac full of the iron-bearing protein called hemoglobin
One cell can contain 250 hemoglobin molecules, each of which can bind 4 oxygen molecules

9. Now, for something completely different
Landweir, Bill. “A Day in the Life of a Red Blood Cell.” Online Posting. YouTube, 17 April Web. 29 October 2011.

10. In the middle, the buffy coat, which contains…
Leukocytes
Platelets

11. Leukocytes White blood cells Defense and immunity Can perform
Diapedesis – can leave and enter the blood stream
Positive chemotaxis – they can travel around the body in response to chemicals that are released from damaged cells. They follow the diffusion gradient of these chemicals to find the injured area.
Leukocytosis – when the body makes more WBC
Leukopenia – abnormally low levels of WBC

12. Types Granulocytes – contain granules Agranulocytes
Neutrophils –phagocytes at sites of acute infection
Eosinophils – helps battle allergies and infections by parasitic worms
Basophils – contain large histomine (inflammatory chemical) containing granules
Agranulocytes
Lymphocytes – Found in lymphatic tissue and plays an important role in immune response
Monocytes – Largest WBC that migrates into tissues, turn into macrophages, which can destroy large amounts of infection.

13. Platelets Irregular cell fragments that originate from megakaryocytes
Used for blood clotting when hemostasis occurs

14. What is hemostasis?
A stoppage of blood flow through broken blood vessels
Steps in hemostasis.
Platelet plug formation – “sticky” platelets cling to damage area and use a chemical to attract more platelets
Vascular spasms – serotonin is also released by platelets. This causes the blood vessel to spasm and narrow, which decreases blood loss
Coagulation (blood clotting) occurs

15. Coagulation Steps Injured tissue releases tissue factor
A chemical, PF3, on the surface of the platelets reacts with the tissue factor and some other ions to form an activator (prothrombin) that starts the clotting cascade.
The activator converts prothrombin into thrombin
The thrombin joins fibrinogen in the area into long, insoluble, hair like molecules called fibrin. This creates a mesh that traps RBC and forms the clot.
Once the clotting cascade starts, factors are triggered to stop widespread clotting

16. Now for “Once Upon a Time…Life: The Tiny Platelets”
“Once upon a time... Life - The tiny platelets.” Online Posting. YouTube, 1 January Web. 29 October 2011.