Ch 20 Flashcards
The three unpaired arteries emerging from the descending abdominal aorta
Supply the gastrointestinal tract
Superior mesenteric artery
Celiac trunk
Inferior mesenteric artery
Baroreceptors
Specialized nerve endings INTERNAL
Respond to stretch in blood vessel walls
Sudden, short term changes in BP
Descending abdominal aorta
Supplies branches to supply the abdominal wall and organs
arterioles
Smallest arteries
Less than 6 layers of smooth muscle in tunica media
Pulmonary circulation
Carbon dioxide removed from blood
Enters alveoli of the lungs
Oxygen exits the alveoli and enters the blood
Tunics
Walls of arteries and veins
3 layers
Capillaries
Smallest blood vessels
Connect arterioles to venules
External iliac artery
Provides main blood supply to the lower limb
Two main Baroreceptors
Aortic arch
Carotid sinuses
Capillary bed components
True capillaries
Metarteriole
Thoroughfare channel
Post capillary venule
Sinusoids in body
Spleen
Bone marrow
Liver
Vasomotion
Precapillary sphincters open when a tissue needs nutrients
Pre capillary sphincters close when the tissue needs are met
Hepatic portal system
Drains GI tract
Shunts blood to liver
Venules
Companion vessels to the arterioles
Sphygmomanometer
Measures BP
Brachial artery
Compressed by the sphygmomanometer when taking BP
Splenic artery contains
Stomach
Pancreas
Spleen
Carotid sinuses
Head
Neck
Elastic arteries
Subclavian artery
Common carotid artery
Aorta
Tunics
Walls of arteries and veins have 3 layers
Chemicals that act as vasodilators
Histamine
Nitric oxide
Bradykinin
Esophageal veins drain into which two veins ?
Left gastric vein
Azygos vein
End arteries
Common pathway
Sinusoids
Capillaries
Large gaps in walls
Discontinuous/absent basement membrane
Continuous capillaries are found
Skin
Muscle
ADH
Vasopressin
Resistance and BP
Hormones help regulate BP
Antidiuretic hormone
Aldosterone
Atrial natriuretic peptide
Common hepatic artery
Supplies the liver, gallbladder, and stomach
Viscosity
Restistance of fluid to its flow
Vasodilation
Widening of blood vessel lumen
Relaxation of smooth muscle of tunica media
Peripheral resistance factors
Blood vessel length
Blood viscosity
Blood vessel radius
Thickest layer of wall in arteries
Tunica media
Vasoconstrictor
Stimulates precapillary sphincters
Decreases local blood flow
Elastic arteries
Largest
Filtration
Bulk flow of fluid out of blood
Reabsorption
Bulk flow into blood
Hepatic veins
Carry blood from lover to inferior vena cava
Arteries
Covey blood from heart to capillaries
Capillaries
Microscopic blood vessels
Exchange substances between blood and tissues
Veins
Drain blood from capillaries
Transport it back into heart
Sub endothelial layer composed of
Areolar CT
Vasa vasorum
Small arteries required to supply large vessels
Thickest layer in veins
Tunica externa
Pathway of blood in portal system
Artery, capillary bed, portal vein, second capillary bed, vein
Net filtration pressure (NFP)
Arterial
Bulk flow out of capillary, plasma leaves
Venous
Bulk flow into capillary, plasma enters
Lymphatic system
Picks up excess fluid
Filters and returns fluid to venous circulation
Local blood flow
Degree of tissue vascularity
Alternating blood flow
Total blood flow
Resistance
Amount of friction blood experiences traveling through vessels
Increased resistance decreases total blood flow
Viscosity
Vessel length
Lumen size
Chemoreceptors
Aortic bodies in arch and charities bodies in EXTERNAL carotids
