What is blood made of ?

Blood is made up of cells and a watery liquid called plasma

It also contains other things like: nutrients (such as sugar) hormones clotting agents waste products to be flushed out of the body.

Plasma is the liquid portion of blood

Plasma is: Transport medium 91.5% water.

Besides water, plasma also contains dissolved salts and minerals like calcium, sodium, magnesium, and potassium.

What kinds of cells do we find in the blood?

There are three kinds of cells in the blood: Red blood cells: carry oxygen from the lungs throughout the body. White blood cells: help fight infection. Platelets: help in clotting

Red Blood Cells (Erythrocytes) Most numerous Give blood its red color Shaped like a doughnut with an indention in the middle instead of a hole Contain special molecules called hemoglobin.

Red Blood Cells (RBCs) = Erythrocytes >99% of total blood cells are RBCs ~5 million/ml Hb (hemoglobin) Fe (iron) Transport O2 and CO2 No nucleus when mature

Hemoglobin Each molecule of hemoglobin contains four iron atoms. Each atom can bind with one molecule of oxygen Each hemoglobin molecule can carry four oxygen molecules.

Hematocrit (or ‘crit, if you want to sound cool) The percent of whole blood made up of red blood cells. Nl value: 40-50% Let’s run a virtual hematocrit http://scienceu.fsu.edu/content/virtuallab/hematology/docs/hematocrit.html

In the capillaries, where there is little oxygen, the hemoglobin readily sheds the oxygen it is carrying and allows it to be absorbed by the body's cells.

Platelets (Thrombocytes) Help blood to clot When bleeding occurs, platelets clump together to help form a clot. Also, when they are exposed to air (as they would be by a wound), platelets start breaking down and release a substance into the bloodstream. This substance starts a chain of chemical events that eventually causes a protein in the blood, fibrinogen, to turn into a different substance, fibrin, which forms long threads. These threads tangle up red blood cells to help form a clot, or scab, over the wound.

Show clotting video at http://www.youtube.com/watch?v=8YjmE5UMYvY

White Blood Cells (leukocytes) Whenever a germ or infection enters the body, the white blood cells snap to attention and race toward the scene of the crime. The white blood cells are continually on the lookout for signs of disease. When a germ does appear, the white blood cells have a variety of ways by which they can attack. Some will produce protective antibodies that will overpower the germ. Others will surround and devour the bacteria.

The white blood cells have a rather short life cycle: days to weeks A drop of blood can contain anywhere from 7000 to 25000 white blood cells at a time. Infection increase that number significantly A consistently high number of white blood cells is a symptom of Leukemia, as many as 50000 wbcs in a single drop

White Blood Cells (WBCs) = Leukocytes There are 5 different types of WBCs…….

Neutrophils Most abundant Phagocytic Kill bacteria

Basophils Release histamine. Their numbers increase in allergic reactions

Eosinophils Fight parasitic infections

Lymphocytes Produce antibodies Fight viruses https://www.youtube.com/watch?v=Tdx-U8S6ZMk

Monocytes Largest of the WBCs Protect against blood born pathogens Phagocytic Large kidney-shaped nucleus

Name the Cells Neutrophils Basophils Eosinophils Lymphocytes Monocytes

Normal Smear

Abnormal Smear

Blood-Type Frequency In the United States: Do you know what type you are?