Respiratory/Circulatory Test

Today we discussed blood. Many students told me they would rather talk about the icky stuff that happens in the digestive system rather than blood!

We discussed what blood is made of and how scabs are formed.  Several students learned why their parents always tell them to keep the band aid off of a cut so the air can get at it. We also discussed blood types.  I completed a demonstration for each class about giving and receiving blood.  I filled eight beakers with water. Two beakers had blue food coloring (type A), two had yellow (type B), two had a mix of yellow and blue to make green (type AB), and two were clear (type O).  I then added vegetable oil to one beaker of each color to represent the Rh factor.  When receiving blood, the colors should not change.  For example, someone who is type B, can't get type A blood...it would change the color of the food coloring.  However, you can add type O blood...that is clear so it won't affect the color.  We also discussed the oil. If your blood doesn't have "oil," you can't receive a type that does...your body doesn't know what it is.  After several different scenarios, each class realized that people with type O- blood really are life savers (they can give blood to anyone).

Our respiratory/circulatory test will be next week Thursday.   Below are some helpful videos for studying.

Marble blood flow            Pumps Your Blood

The study guide has been linked to the homework doc.

Study hard this weekend!