Instructions: Italicized questions require use of the Nelson text, pp. 250-253 and pg. 257.

1. Obtain a microscope and microscope slide of "Artery, Capillary, and Vein". The vessels have been stained to make them more visible.


2. Identify the artery, vein, and capillary. Start out on low power and move to medium and high power when necessary. State one visible feature which helps you identify each type of vessel.


• artery: ______________________________________


• vein: ______________________________________


• capillary: ______________________________________


3. Focus in on the artery. The tunica intima is a very thin, squiggly, dark blue/purple line. The tunica media lies just outside the tunica intima. It is a pinkish colour. Observe this layer on medium and high power noting the concentric (circular) rings.


• What do you think the rings are (hint: they enable the artery wall to contract)? ______________________


• Which layer is most proximal to the lumen? ___________________________


• Would this artery likely carry oxygenated or deoxygenated blood? ________________________


• What colour is the tunica externa? ________________________


• What kind of smaller blood vessels do arteries immediately lead into? __________________


• What is the name for the specific condition where fat deposits on the arterial wall cause plaque formation which blocks the lumen? ___________________________


• What is the name for the general group of disorders that cause blood vessels to thicken, harden, and lose their elasticity? ___________________________


• What is the name for the disorder in which the inner wall of an artery weakens and bulges out, sometimes bursting? _______________________



Draw a cross section of an artery on blank white paper and attach to this lab (pencil only, use a ruler to label the 3 major layers and the lumen).


4. Focus in on the vein.


• Would this vein likely carry oxygenated or deoxygenated blood? ______________________


• What kind of smaller blood vessels lead immediately into veins? ________________________


• What kind of smaller blood vessels do veins immediately lead into? ________________________


• What are the two structures that work together to keep venous blood moving back to the heart? ___________________________ and _________________________


5. Focus in on the capillary.
You may have to search around on the slide using medium or high power looking for a very small hole. Often, capillaries can be found in the purple masses of muscle and connective tissue near the edge of the slide.

• What major layer(s) does the capillary have? _____________________________


• How many cells thick is a capillary? ________________________


• Why is it important for a capillary to be extremely thin-walled? _________________________________________________


• What kind of blood vessels lead immediately into capillaries? ________________________


• List 2 things that can cause rupturing of a capillary? _________________________ and ___________________________


6. Complete the table (use Fig. 5 on pg. 254).
   

   Description	Name of Blood Vessel
   carries blood into arm
   carries blood out of arm
   carries blood into head
   carries blood out of head
   carries blood into upper leg
   carries blood out of upper leg
   carries blood carries blood into kidney
   carries blood out of kidney
   carries blood into liver
   carries blood out of liver

   
   

7. Complete the table (use Fig. 2 on pg. 257).
   

   Blood Vessel	Chamber of Heart Connected To?	Oxy. or Deoxy. Blood?
   pulmonary artery
   pulmonary vein
   aorta
   superior vena cava
   inferior vena cava