Watch these videos of blood flow in the web of a frog’s foot, and then answer the questions asked for lab write up assignment.
(1) What were your general impressions as you watched these videos of blood flow through blood vessels in a frog’s web?
(2) Which of these three would have the smallest diameter (width): arterioles, capillaries or venules?
(3) Did you recognize any capillaries in the videos of the frog’s web? How did the width of the capillary compare to the size of the red blood cells flowing through it?
(4) What are some qualities that should allow you to distinguish between arterioles and venules in a microscopic examination, such as this one? In particular, which one of these two would have thinner walls?
(5) If you were looking at a capillary, which direction would you expect to see blood flow? In other words, would you see blood flow towards the arteriole or towards the venule?
(6) Were you able to distinguish between arterioles and venules when you observed the vessels in the web of the frog’s foot? How were you able to distinguish between these two types of vessels? What were some clues that you used to identify each type? (Hint: see your answers to questions 4 and 5.)
(7) What differences did you note in the rate of blood flow through the arterioles, capillaries, and venules? Where was it moving fastest? Where was slowest?