Unformatted text preview: Blood vessels Figure 15-1 Blood vessel structure note this figure is NOT to scale Figure 15-2 Angiogenesis development of new blood vessels stimulated by cytokines (local chemical signal by smooth muscle cells and pericytes) Figure 15-3 Blood pressure Review: Blood flows from higher pressure to lower pressure. The heart generates pressure. Figure 15-5 Measuring blood pressure - sphygmomanometer Figure 15-7 Blood pressure MAP = 2/3 diastolic + 1/3 systolic pressure Figure 15-5 Blood pressure regulation Figure 15-9 Circulatory system branches Blood flow distribution will change with demand (figure shows at rest) Can have increase in one branch with decrease in another Figure 15-14 Figure 15-15a Capillaries differ in how leaky they are most common e.g. kidney, intestine
Figure 15-17 The "blood-brain barrier" (pp. 303, 305 Ch. 9) Fig. 9-6 400 miles of capillaries in brain •not very permeable •protects brain from toxins •transporters in membranes move nutrients and wastes permeable exceptions: hypothalamus, vomiting center in brain stem Neural tissue has special metabolic requirements (pp. 305-306 Ch. 9) Neurons require constant supply of oxygen and glucose. Brain function diminishes almost immediately without oxygen or glucose (damage may occur within minutes). Brain consumes large fraction of total body glucose consumption (50%?).
Figure 15-14 ...
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- Spring '10
- Physiology, Blood vessel