Blood Vessels to Vein journey
Start from base of Heart (Left Ventricle)
Ends at Right Atrium of Heart
What does the thickness of a vessels wall indicate?
It depicts the amount of pressure the vessel is designed to withstand.
What does the sympathetic stimulation cause in a blood vesssel?
Contractions, known as vasoconstriction
Lack of stimuli from PARA, leads to vasodialation (widening of lumen)
Fight of Flight
-increases heart rate
-liver releases sugars into blood
Rest and Digest
-blood flow to GI increases
-Smaller than arteries
-Composed mostly of smooth muscle
-fewer than 5 layers of sm. muscle
-control blood distribution to various regions of body by contracting and relaxing of their smooth muscle
-Single Layer of squamous epithelial cells
-lot of cap. in muscle and nervous tissue
- few in cornea & cartiladge
- Form capillary beds.
-Regulate flow into capillary bed
-solutes cross capillary wall by diffusion
-plasma proteins stay (too big) so they help with osmotic pressure.
The filtration forces the formation of fluid in the interstitial space and results in hydrostatic pressure
Increased pores for
fenestrated, the endothelial cells have large gaps (fenestrae) in them....thereby increasing the 'leakiness' of the capillary
What is the composition of a capillary?
a single layer of squamous epithelium and a basement membrane
(come after capillaries in bed in flow)
-Merge to form veins
-tunica media and adventitia composed of LCT
-Carry blood towards the heart
-path of veins parrallels that of arteries
-Same 3 layers as arteries (much smaller TUNICA MEDIA)
-blood pressure is lower than in arteries
-blood may pool as reservoir
-tunica adventitia exhibits smooth muscle
What is the function of valves in the vascular system?
permit unidirectional flow (prevent backflow)
What is the purpose of having smooth muscle in tunica adventitia in veins?
TO massage blood back to the heart
Right coronary Artery(green)
Left Coronary artery (purple)
-provides oxygenated blood to the heart muscle
There are two types of coronary circulations
-On posterior surface of heart
-within the interventricular septum
Within interventricular septum...
branch of the anterior
and posterior interventricular
portal: takes venous blood from the digestive tract to the liver for processing 3. pulmonary: 4. systemic:
Pathway of pulmonary circulation
O2 starved bllod from body goes to Right atrium then to right ventricle and out to the lungs
From lungs to heart...
Once oxygenated (the blood) by the lungs, the blood enters the Left Atrium, through the left ventricle and back to the body.
Why is the venous blood from the GI filtered through liver via portal circulatory circuit?
-to remove wastes absorbed by the gut
-store nutrients in liver (glucose, glycogen)
Portal Veins is formed when ....
the 3 veins that drain the intestinal tract join together
Where does the portal vein deliver blood to?
It delivers blood to liver for filtration before it is returned to vena cava.
Systemic circulation Arteries
Descending aorta intercostal (thoracic)
Aortic Arch (Heart)
Common iliac (Iliium)
External Iliac (Iliium)