Lesson 1 (MIDTERMS) Flashcards
(88 cards)
The blood vessels of the body form a network more complex than an interstate highway system.
Circulatory System
Enumerate 5 functions of circulatory system
- Carries blood
- Exchanges nutrients, waste products, and gases with tissues
- Transports substances
- Helps regulate blood pressure
- Directs blood flow to the tissues
Functions of circulatory system. Blood vessels carry blood from the heart to all the tissues of the body and back to the heart.
Carries Blood
Nutrients and O2 diffuse from blood vessels to cells in essentially all areas of the body.
Exchanges Nutrients, Waste Products, and Gases with Tissues
Functions of circulatory system. Blood transports hormones, components of the immune system, molecules required for coagulation, enzymes, nutrients, gases, waste products, and other substances to and from all areas of the body.
Transports Substances
Functions of circulatory system. The circulatory system and the heart work together to regulate blood pressure within a normal range.
Helps Regulate Blood Pressure
Functions of circulatory system. The circulatory system directs blood to tissues when increased blood flow is required to maintain homeostasis.
Directs Blood Flow to the Tissues
The highest, normal blood pressure reading _____
120 (diastolic) /80 (systolic)
- Carry blood away from the heart.
- Usually, the blood is oxygenated (oxygen-rich).
- Blood is pumped from the ventricles of the heart into large, and elastic arteries.
- As they become smaller, the artery walls undergo a gradual transition from having more elastic tissue than smooth muscle to having more smooth muscle than elastic tissue
Arteries
- Diameter arteries and have the thickest walls.
- Greater proportion of their walls is composed of elastic tissue, and a smaller proportion is smooth muscle.
- The aorta and pulmonary trunk are examples of _____.
Elastic Arteries
- Medium-sized and small arteries
- Walls of medium-sized arteries are relatively thick compared to their diameter
- Most of the wall’s thickness results from smooth muscle cells of the tunica media
Muscular Arteries
- Contraction of the smooth muscle in blood vessels
- Decreases blood vessel diameter and blood flow
Vasoconstriction
- Relaxation of the smooth muscle in blood vessels
- Increases blood vessel diameter and blood flow.
Vasodilation
- Transport blood from small arteries to capillaries
- The smallest arteries in which the three tunics can be identified.
- The tunica media of ____ consists of only one or two layers of circular smooth muscle cells.
Arterioles
- Where blood flows from the arterioles
- Where exchange of substances such as O2, CO2, nutrients, and other waste products occurs between the blood and the tissue fluid.
Capillaries
- Where blood flows from the capillaries
- Carry blood toward the heart
- Usually, the blood is deoxygenated (oxygen-poor).
- Compared to arteries, the walls of ____ are thinner and contain less elastic tissue and fewer smooth muscle cells
Veins
- Have a diameter slightly larger than that of capillaries and are composed of endothelium resting on a delicate connective tissue layer
Venules
- Small veins are slightly larger in diameter than venules.
- Medium-sized veins collect blood from small veins and deliver it to large veins
Small and Medium Veins
- Veins that have diameters greater than 2 mm contain valves, which ensure that blood flows toward the heart but not in the opposite direction
Large Veins
System of blood vessels that carries blood from the right ventricle of the heart to the lungs and back to the left atrium of the heart.
Pulmonary Circulation
System of blood vessels that carries blood from the left ventricle of the heart to the tissues of the body and back to the right atrium.
Systemic Circulation
Where the arteries of the systemic circulation branch directly or indirectly.
Aorta
- Part of the aorta that passes superiorly from the left ventricle.
- The right and left coronary arteries arise from the base of the ________ and supply blood to the heart
Ascending Aorta
Aortic Arch. Enumerate 3 major arteries, which carry blood to the head and upper limbs that originate from the aortic arch:
- Brachiocephalic Artery
- Left Common Carotid Artery
- Left Subclavian Artery