1. Blood Vessels basic vessel anatomy maintaining constant blood pressure
aneurisms
variations in circulatory pathways
examples of portal systems
blood supply to the brain

2. Tunica intima Tunica media Tunica externa endothelium BM smooth muscle
collagen
some elastin
L. vein
L. artery
Tunica externa
loose CT
vasa vasorum
Medium sized vein
Medium sized artery
venule
arteriole
capillary

3. To heart
Valve
open
Vein
Valve
closed
Contracted skeletal
muscles
Relaxed skeletal
muscles

4. Precapillary sphincters Sphincters open Sphincters closed
When are sphincters closed? Fingers? Muscles? Around gut?
Sphincters open
Sphincters closed

5. Hepatic portal system Portal system (2 capillary beds) IVC Hepatic
sinusoids
Gastric veins
spleen
pan
Superior
Mesenteric V
Hepatic portal system

6. Portal system
Arteriovenous
anastomosis
Arterial anastomoses
Venous anastomoses
Dark blue = portal light blue = systemic

7. Internal carotid
Basilar
Circle of Willis
Vertebral
Cerebrovascular Accident = CVA = stroke

9. Aneurysm:
weak point in an artery or
heart wall
common in abdominal aorta
renal arteries & brain

10. Cerebral vascular accident (CVA) = stroke

11. How to maintain constant blood pressure
1. Conducting arteries expand & recoil
With increasing and decreasing pressure
2. measure pressure,
adjust HR and dilate
or constrict BV’s
High BP
Lower HR

12. Fig. 21.4(TE Art) Carotid body Baroreceptors Aortic body Baroreceptors
Carotid sinus
Baroreceptors
Common carotid
artery
Aortic body
Aortic arch
Baroreceptors

13. Fig. 16.1(TE Art) Glossopharyngeal Nerve (CN IX) Baroreceptors
sense increased
blood pressure
Vagus nerve
(CN X)
Heart rate
decreases