Vessel physiology

Large arteries near the heart, high in elastin, acting as pressure reservoirs to maintain continuous blood flow.

Medium-sized arteries distributing blood to organs and tissues; control blood flow via smooth muscle.

Small arteries controlling systemic blood pressure and blood flow into capillary beds through constriction/dilation.

The largest artery, part of the elastic artery system, originating from the heart and conveying blood to the rest of the body.

Small vessels regulating blood flow into individual capillaries; fine-tuning blood supply to tissues.

The outermost layer of a vein, composed mainly of collagen and elastic fibers.

Small veins that collect blood from capillaries.

Valves in veins that prevent backflow of blood. Especially common in limbs due to low pressure.

The study of blood flow in the body.

Describes how blood flows in small vessels, relating flow rate to vessel size and pressure.

Opposition to blood flow, influenced by vessel radius, length, and viscosity.

Small vessels that supply blood to the walls of large blood vessels.

The calf muscles act as a "second heart" to help pump blood back up the body

Blood flow characterized by swirling and disordered motions, not smooth and predictable

Conditions that cause disease or abnormal changes in the body.

Pressure and velocity are inversely proportional in a fluid system; higher velocity leads to lower pressure.

Blood pressure is highest in the aorta and large arteries (typically 120 mmHg during systole)

Blood velocity is high in large arteries due to the heart's pumping; it decreases as the blood enters the smaller arteries and arterioles.

Pressure drops significantly in capillaries, usually around 30mmHg or less crucial for nutrient and waste exchange.

Blood velocity in capillaries is the slowest to allow time for exchange; larger cross-sectional area also contributes.

Atherosclerosis, stenosis, hypertension, aneurysms, and valvular heart disease can all contribute to increased turbulent flow.

Veins' ability to expand and store extra blood without significant pressure increase.

The portion of blood volume in the heart, vena cavae, and pulmonary circulation (approximately 25%).

Blood contained in veins outside the central compartments, like those in limbs and abdominal cavity.

Gravity shifts blood from central circulation to peripheral veins when changing from lying to standing position.

Giving extra IV fluid to someone with congestive heart failure (CHF) can worsen fluid overload in the body, which is a common problem in CHF cases

Multiple vessels, like capillaries, arranged in parallel, creates lower cumulative resistance, enabling efficient blood flow and nutrient exchange.

About 80% of an adult male's blood volume is in the systemic circulation, with a significant portion in the systemic veins.

Veins' ability to expand and hold more blood without a significant pressure increase.

Arteries' ability to stretch and expand during blood pressure increases (systole).

Changes in diameter due to pressure in a blood vessel, the ability of a blood vessel to expand and accommodate changes in blood volume or pressure.

The relatively less opposition to blood flow in veins, compared to capillaries, due to their larger diameter, enabling efficient return of blood to the heart.

Blood vessels, especially larger arteries, become stiffer and less compliant with age due to factors like atherosclerosis and calcification.

A small portion (~20%) of the blood volume is found in small arteries and capillaries.

Capillaries' ability to adjust their own blood flow based on local tissue needs, independent of overall blood pressure.

The process where the smooth muscle in blood vessels responds to pressure changes to maintain consistent tissue blood flow.

Difference in concentration of a substance across a membrane, driving diffusion.

Smaller molecules that dissolve easily in the membrane and a higher permeability barrier increases flow.

Albumin and other plasma proteins, glycosaminoglycans, and lymphatics help prevent excess fluid retention in tissues.

The rate at which molecules move across a membrane from point A to point B.

Capillaries' self-regulation of blood flow based on local signals, like tissue needs.

Significant drop in pressure within capillaries, crucial for exchange of nutrients and waste products.