Chapter 21 Blood Vessels and Circulation

These flashcards cover the key concepts from Chapter 21 on blood vessels and circulation, focusing on anatomy, physiology, and dynamics of blood circulation.

What are the major arteries of the upper limb?

Subclavian, Axillary, Brachial, Radial, Ulnar.

What is the function of the circulatory system?

Carries blood to body tissues, exchanges nutrients, waste products, and gases, regulates blood pressure, and controls blood flow.

What are the three main types of blood vessels in the circulatory system?

Arteries, veins, and capillaries.

What are the types of circulation in the body?

Pulmonary and systemic circulation.

What is the pathway of blood flow in pulmonary circulation?

Blood flows from the right ventricle, through the pulmonary trunk, to the lungs, then to the left atrium.

What are the layers of blood vessel structure?

Tunica externa, tunica media, and tunica intima.

What function does the tunica media serve in blood vessels?

It is composed of smooth muscle that regulates the diameter of the vessel and is responsible for vasoconstriction and vasodilation.

How do capillaries facilitate the exchange of substances?

Substances cross capillary walls by diffusion either through or between endothelial cells.

What are the three types of capillaries?

Continuous, fenestrated, and sinusoidal.

What is an anastomosis in the circulatory system?

The connection between two or more blood vessels that allows for alternative pathways for blood circulation.

What are the major veins that drain the head and neck?

External jugular veins and internal jugular veins.

What is the hepatic portal system?

A system of veins that carry nutrient-rich blood from the gastrointestinal tract to the liver.

What do valves in veins do?

Prevent backflow of blood.

What are the three major hormones involved in blood pressure regulation?

ADH (Antidiuretic Hormone), Aldosterone, and Atrial Natriuretic Hormone (ANP).

What happens during vasodilation?

Blood vessels widen, leading to decreased blood pressure.

What are Korotkoff sounds?

Sounds produced during the measurement of blood pressure, indicating blood flow through arteries.

What is mean arterial pressure (MAP)?

The average blood pressure in a person's arteries during one cardiac cycle.

What role does blood viscosity play in circulation?

It affects the resistance to blood flow within the vessels.

What is the function of precapillary sphincters?

They regulate blood flow into capillary networks.

What is the pathway of blood flow in systemic circulation?

Blood flows from the left ventricle, through the aorta and systemic arteries, to the body tissues, then to the right atrium via systemic veins.

What are the key structural and functional differences between arteries and veins?

Arteries carry blood away from the heart, typically have thicker, more muscular walls to withstand high pressure, and usually carry oxygenated blood (except pulmonary artery). Veins carry blood towards the heart, have thinner walls, larger lumens, and often contain valves to prevent backflow, typically carrying deoxygenated blood (except pulmonary vein).

Define systolic and diastolic blood pressure.

Systolic pressure is the maximum pressure exerted on arterial walls during ventricular contraction (systole). Diastolic pressure is the minimum pressure exerted on arterial walls during ventricular relaxation (diastole).

What are the two main types of arteries?

Elastic (conducting) arteries and muscular (distributing) arteries.

What factors influence peripheral resistance in blood vessels?

Factors include vessel diameter (most significant), blood viscosity, and total vessel length.