BIO307 - Test #3 - Chapter 15 - Blood Flow and Blood Pressure

Arteriole

one of the small thin-walled arteries that end in capillaries

Venule

a minute vein continuous with a capillary

angiogenesis

the formation of new blood vessels, sometimes due to the presence of a tumor

coronary heart disease

a heart disease due to an abnormality of the arteries that supply blood and oxygen to the heart

systolic pressure

the blood pressure during the contraction of the left ventricle of the heart

diastolic pressure

the blood pressure after the contraction of the heart while the chambers of the heart refill with blood

Mean Arterial Pressure

represents the driving pressure
MAP = diastolic pressure + (1/3) (Systolic P / diastolic P)

Peripheral Resistance

resistance to blood flow offered by the arterioles

Baroreceptors

Monitor blood pressure in the aorta and carotid artery, trigger baroreceptor reflex (primary reflex control pathway for homeostatic control of MAP)

Fenestrated Capillary

pores that allow large volume of fluid to pass rapidly

Ex: Intestines, Kidney

Artherosclerosis

inflammatory condition in which fatty deposits of plaques develops in arteries. Unstable plaques can cause arteries to be blocked by triggering blood clots.

Eg: McDonalds

Blood Vessels Vary in Size/Structure

Artery: 0.1-10 mm diameter, 1 mm wall thick
Arterioles: 10-100 micrometers diameter, 6 micrometers thick
Capillaries: 4-10 micrometers diameter, 0.5 micrometer thick
Venules: 10-100 micrometers diameter. 1 micrometer thick
Veins: 0.1 - 100+ mm diameter, 0.5 mm thick

Predict Dilation/Constriction of Arterioles due to Sympathetic NS:

(Puma example)

How High/Low MAP is Detected AND Corrected

Baroreceptors detect the high blood pressure, and provide signaling that either increases or decreases blood pressure accordingly (see image for pathway)

Kidney + BP

Kidney produces urine, which removed blood volume, could be the response to baroreceptor detection of higher than normal BP

Fenestrated Capillary Location

mainly in the kidney or the intestines, where they are associated with absorptive transporting epithelia

These areas process large amounts of liquid:
Kidney needs large pores to allow passing of urine
Intestines need to be able to absorb and transport for retention of ingested water

Slow vs Fast Blood Flow

Capillaries: blood flow is very slow, RBC are single file for gas exchange to happen

Arterioles: faster blood flow

Lymphatic System Function

a network of vessels that drains lymph from tissues into blood, returns fluid to circulatory system from capillaries

Edema: condition in which excess fluid accumulates in the interstitial space, affects normal balance between capillary filtration and absorption