Classification of vessels:Conducting - large arteries arising from heart and their branches. Elastic Distributing - smaller arteries reaching individual organs or regions. Muscular Resistance - arterioles, main source of peripheral resistance to blood flow. MuscularExchange - collective term for capillaires, sinusoids, postcapillary venules. Site of

gas/nutrient exchangeReservoir - large venules and veins. Large volume, low pressure, convey blood back

to heart.

Anastomoses - junction of two or more arteries serving same body part (collateral circulation)

Vasa Vasorum – microcirculatory vessels in walls of large blood vessels (walls > 1mm)

Aorta sizes:human = 30mm (1 in.)mouse = 2mmblue whale = 30cm (15 in)

Transparency leg/foot

Hepatic-portal circulation