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
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
