The microcirculation, the lymphatic system and local blood flow control mechanisms,

Topic: The
Microcirculation, The
Lymphatic System
and Local Blood Flow
Control Mechanisms
Course: 317
Textbook(s): Guyton
(p 189-201), Widmaier
(p. 396-409)

, Questions Notes

The most purposeful function of the microcirculation is:

. 1. Name the functions of  transport of nutrients to the tissues and,
the microcirculation. G. p.  the removal of cell excreta
189
The microcirculation of each organ is organized to serve the
organs specific needs.

Artery:

 Each nutrient artery entering an organ branches 6-8
times before they become small to be called
arterioles- internal diameter of 10-15 micrometers.
 the arterioles than branch 2-5 times-diameters of 5-9
micrometers at the end where they supply blood to
the capillaries.

Arterioles:

 highly muscular
 diameters change manyfold.
2. Describe the structure of  the terminal arterioles-metarterioles do not have a
the microcirculation. G. p. continuous muscular coat, but smooth muscular
190. fibres encircle the vessel at intermittent points.
 At this point, a precapillary sphincter is found. A
smooth muscle fibre encircling the capillary. This
sphincter can open and close the entrance to the
capillary.

Veins:

 The venules are larger than the arterioles and have a
weak muscular coat.
 pressure much lower than in the arterioles.
 still contract despite the weak muscular wall




3. Describe the structure of Endothelial cells found in the capillary wall.
the capillary wall. G. p. 190. The wall is composed of:

 unicellular layer of endothelial cells