BIOL 2823 Cardiovascular system

Arteries: carry blood away from the heart; thicker connective walls than veins

Arterioles: smallest branches of arteries

Capillaries: blood vessels where diffusion between blood and interstitial fluid occurs; tunica intima only

Veins: carry blood towards the heart; contain majority of the bodies blood

Venules: smallest branches of veins

Diameter of blood vessels: larger close to the heart; smaller far from the heart

Three layers of vein/artery walls: tunica intima, tunica media, tunica externa

Tunica intima: endothelium, connective tissue, elastic fibers

Tunica media: Sheets of smooth muscle; contraction and relaxation of blood vessel

Tunica externa: Connective tissue mixed with adjacent tissues; stability of blood vessel

Elastic arteries: largest; more elastic to accommodate for blood leaving the heart

Muscular arteries: blood distribution to extremities; main layer is tunica media

Large veins: similar to elastic arteries

Medium-sized veins: similar to muscular arteries, except main layer is tunica externa

Types of capillaries: Continuous, Fenestrated, Sinusoid

Pulmonary circulation: Between heart and lungs

Systemic circulation: Heart and rest of the body

Vessel cross-sectional area: lower diameter = higher cross-sectional area

Velocity: Arteries(highest) → veins → capillaries

Blood pressure: Arteries(highest) → capillaries → veins

Autoregulation: changes in the blood flow patterns of capillary beds to maintain homeostasis

Vasodilators: promote dilation of precapillary sphincters

Baroreceptors: adjust cardiac output to maintain adequate blood flow to vital tissues and organs

Chemoreceptors: monitor pH levels and dissolved gases (CO2)

Endocrine regulation: responses of the sympathetic nervous system when homeostasis is disturbed

Anti diuretic hormone (ADH): hormone for water retention in the kidneys

Pulmonary circuit: right ventricle → pulmonary trunk → pulmonary capillaries → lung alveoli (gas exchange) → left atrium

Vena cava: two largest veins; enter into the right atrium

Carotid arteries: blood supply to brain

Subclavian arteries: blood supply to arms

Aortic arch: artery that curves over the top of the heart

Ascending aorta: part of aortic arch that flows upwards

Descending aorta: extension of aortic arch that flows downward

Three arteries attached to aortic arch: Brachiocephalic trunk, left common carotid artery and left subclavian artery

Renal artery: artery for kidneys

Gonadal artery: artery for pelvic region

Mesenteric artery: pancreas, small intestine, most of large intestine

Iliac arteries: blood supply to pelvis(internal) and legs(external)

Femoral artery: extension of iliac arteries into upper leg(femur)

Jugular veins: blood supply from head

Iliac veins: blood supply from pelvis(internal) and legs(external)