Circulatory System 05

A longitudinal section of the vena cava is shown here. Note that the longitudinally oriented bundles of smooth muscle in the tunica adventitia have been sectioned parallel to their long axes. How would these muscle fibers appear if this blood vessel had been cut in cross section? The boundary between the adventitia (left) and the media (center-right) is indistinct, but the smooth muscle cut in cross section (at the *) is in the media.

Slide K-5, field N10 of finder slide A, 6.3X objective.