Unit 4 Flashcards
Open System (circulatory)
blood kept in hemolymph, not vessels
Ostia
suck hemolymph inside and draw it forward when the heart is relaxed; openings in the heart or aorta of some animals that allow blood or hemolymph to enter or exit the circulatory system
Closed System (circulatory)
blood is kept in vessels, heart pressurizes the entire system
Vascular Circulatory System
network of blood vessels and the heart that deliver oxygen, nutrients, and other substances to the body’s cells and organs
Vasculature
the blood vessels or arrangement of blood vessels in an organ or part
Arteries
carry blood away from the heart, high pressure with very thick walls
Coronary arteries
bring oxygen away from the heart
Coronary veins
bring oxygen toward the heart
Arterioles
smaller arteries with less thick walls, control blood pressure and blood flow; there are muscles inside that contract and make smaller or lengthen and make larger
Capillaries
smallest blood vessel in the body; when blood goes through it tends to sap all the pressure; gas exchange occurs between capillary and tissue
Venules
small veins, much less muscle, bring veins toward the heart
Endothelium
epithelium that lines blood vessels
Vasoconstriction
squeeze and raise pressure, this occurs anytime a blood vessel is getting smaller in diameter; this is happening when you are getting pale
Vasodilation
heat is getting dumped out (face is red), widening of blood vessels which increases blood flow and lowers blood pressure
Atria
muscle chamber and pump of the heart, pumps blood to the ventricles
Ventricle
muscle chamber of the heart, generates pressure
Systole
contraction phase, more pressure during this phase
Diastole
relaxation phase
Lub
AV valves closing (ventricular systole)
Dup
Semi-lunar valves closing (ventricular diastole)
Cardiac Conduction
electrical flow through the heart
Intercalated discs
connect cardiac muscles
Desmosomes
[cardiac] intermembrane proteins that can grasp each other; hold cells together and contain cadherins
Cadherins
proteins that help cells stick together