Copyright © 2004 Lippincott Williams & Wilkins Chapter 15 Blood Vessels and Blood Circulation

Copyright © 2004 Lippincott Williams & Wilkins The Vascular System Closed system Blood vessels Four heart chambers

Copyright © 2004 Lippincott Williams & Wilkins Blood Vessels Five types of blood vessels Arteries Arterioles Capillaries Venules Veins

Copyright © 2004 Lippincott Williams & Wilkins Checkpoint 15-1: What are the five types of blood vessels?

Copyright © 2004 Lippincott Williams & Wilkins Blood Circuits Two groups of blood vessels The pulmonary circuit Pulmonary artery and its branches Capillaries in lungs Pulmonary veins The systemic circuit Aorta Systemic capillaries Systemic veins

Copyright © 2004 Lippincott Williams & Wilkins Blood flow in a closed system of vessels. Oxygen content changes as blood flows through the capillaries. Zooming In u Judging from color coding, which vessels pick up oxygen? Which vessels release oxygen?

Copyright © 2004 Lippincott Williams & Wilkins Checkpoint 15-2: What are the two blood circuits and what areas does each serve?

Copyright © 2004 Lippincott Williams & Wilkins Vessel Structure Three tunics (coats) of arteries and veins Inner (endothelium) Middle (smooth [voluntary] muscle) Controlled by autonomic nervous system Thinner in veins Outer (supporting connective tissue)

Copyright © 2004 Lippincott Williams & Wilkins Sections of small blood vessels. Drawings show the thick wall of an artery, the thin wall of a vein, and the single-layered wall of a capillary. A venous valve also is shown. The arrow indicates the direction of blood flow. Zooming In u Which vessels have valves that control blood flow?

Copyright © 2004 Lippincott Williams & Wilkins Checkpoint 15-3: What type of tissue makes up the middle layer of arteries and veins, and how is this tissue controlled? Checkpoint 15-4: How many cell layers make up the wall of a capillary?

Copyright © 2004 Lippincott Williams & Wilkins Systemic Arteries The aorta Largest artery Receives blood from left ventricle Branches to all organs

Copyright © 2004 Lippincott Williams & Wilkins The Aorta and Its Parts Ascending aorta Aortic arch Thoracic aorta Abdominal aorta

Copyright © 2004 Lippincott Williams & Wilkins The aorta and its branches. Zooming In u How many brachiocephalic arteries are there? Principal systemic arteries.

Copyright © 2004 Lippincott Williams & Wilkins Branches of the Ascending Aorta and Aortic Arch Ascending aorta Left and right coronary arteries Aortic arch Brachiocephalic artery Right subclavian artery Right common carotid artery Left common carotid artery Left subclavian artery

Copyright © 2004 Lippincott Williams & Wilkins Branches of the Thoracic Aorta Branches to chest wall, esophagus, and bronchi Intercostal arteries

Copyright © 2004 Lippincott Williams & Wilkins Branches of the Abdominal Aorta Celiac trunk Left gastric artery Splenic artery Hepatic artery Superior mesenteric artery Inferior mesenteric artery Paired lateral branches Phrenic arteries Suprarenal arteries Renal arteries Ovarian and testicular arteries Lumbar arteries

Copyright © 2004 Lippincott Williams & Wilkins Checkpoint 15-5: What are the subdivisions of the aorta, largest artery?

Copyright © 2004 Lippincott Williams & Wilkins The Iliac Arteries and Their Subdivisions Internal iliac arteries External iliac arteries Femoral artery Popliteal artery Tibial arteries Dorsalis pedis

Copyright © 2004 Lippincott Williams & Wilkins Arteries That Branch to the Arm and Head External carotid artery Internal carotid artery Subclavian artery Vertebral artery Axillary artery Brachial artery Radial artery Ulnar artery

Copyright © 2004 Lippincott Williams & Wilkins Checkpoint 15-6: What arteries are formed by the final division of the abdominal aorta?

Copyright © 2004 Lippincott Williams & Wilkins Anastomoses Communication between two vessels Circle of Willis Superficial palmar arch Mesenteric arches Arterial arches

Copyright © 2004 Lippincott Williams & Wilkins Arteries that supply the brain. The bracket at right groups the arteries that make up the circle of Willis.

Copyright © 2004 Lippincott Williams & Wilkins Checkpoint 15-8: What is an anastomosis?

Copyright © 2004 Lippincott Williams & Wilkins Systemic Veins Superficial veins Cephalic, basilic, median cubital veins Saphenous veins Deep veins Femoral and iliac vessels Brachial, axillary, subclavian vessels Jugular veins Brachiocephalic vein

Copyright © 2004 Lippincott Williams & Wilkins The Venae Cavae and Their Tributaries Superior vena cava Head, neck, upper extremities Azygos vein Chest wall Inferior vena cava Right, left veins from paired parts, organs Unpaired veins from spleen, digestive tract

Copyright © 2004 Lippincott Williams & Wilkins Principal systemic veins. Zooming In u How many brachiocephalic veins are there?

Copyright © 2004 Lippincott Williams & Wilkins Checkpoint 15-9: Veins are described as superficial or deep. What does superficial mean? Checkpoint 15-10: What two large veins drain the systemic blood vessels and empty into the right atrium?

Copyright © 2004 Lippincott Williams & Wilkins Venous Sinuses Coronary sinus Cranial venous sinuses Cavernous sinuses Petrosal sinuses Superior sagittal sinus Confluence of sinuses Transverse sinuses (lateral sinuses)

Copyright © 2004 Lippincott Williams & Wilkins Cranial venous sinuses. The inset shows the paired transverse sinuses, which carry blood from the brain to the jugular veins.

Copyright © 2004 Lippincott Williams & Wilkins Checkpoint 15-11: What is a venous sinus?

Copyright © 2004 Lippincott Williams & Wilkins The Hepatic Portal System Carries blood from abdominal organs to liver Superior mesenteric vein Splenic vein Gastric, pancreatic, inferior mesenteric veins Sinusoids

Copyright © 2004 Lippincott Williams & Wilkins Hepatic portal system. Veins from the abdominal organs carry blood to the hepatic portal vein leading to the liver. Arrows show the direction of blood flow. Zooming In u What vessel do the hepatic veins drain into?

Copyright © 2004 Lippincott Williams & Wilkins Checkpoint 15-12: The hepatic portal system takes blood from the abdominal organs to what organ?

Copyright © 2004 Lippincott Williams & Wilkins The Physiology of Circulation Blood exchanges oxygen, carbon dioxide, other substances generated by cells Tissue fluid (interstitial fluid) is exchange medium

Copyright © 2004 Lippincott Williams & Wilkins Connection between small blood vessels through capillaries. The blood delivers oxygen (O2) to the tissues and picks up carbon dioxide (CO2) for transport to the lungs. Note the lymphatic capillaries, which aid in tissue drainage.

Copyright © 2004 Lippincott Williams & Wilkins Capillary Exchange How substances move between cells and capillary blood Diffusion Main process Blood pressure Moves material into tissue fluid Osmotic pressure Moves material into capillaries

Copyright © 2004 Lippincott Williams & Wilkins Checkpoint 15-13: As materials diffuse back and forth between the blood and tissue fluid across the capillary wall, what force helps to push materials out of the capillary? What force helps to draw materials into the capillary?

Copyright © 2004 Lippincott Williams & Wilkins The Dynamics of Blood Flow Vasomotor center in medulla regulates vasomotor activities Vasodilation Vasoconstriction Precapillary sphincter

Copyright © 2004 Lippincott Williams & Wilkins Checkpoint 15-14: Name the two types of vasomotor changes. Checkpoint 15-15: Where are vasomotor activities regulated?

Copyright © 2004 Lippincott Williams & Wilkins Return of Blood to the Heart Mechanisms that promote blood’s return to heart Contraction of skeletal muscles Valves Breathing

Copyright © 2004 Lippincott Williams & Wilkins Role of skeletal muscles and valves in blood return. (A) Contracting skeletal muscle compresses the vein and drives blood forward, opening the proximal valve, while the distal valve closes to prevent backflow of blood. (B) When the muscle relaxes again, the distal valve opens, and the proximal valve closes until blood moving in the vein forces it open again. Zooming In u Which of the two valves shown is closer to the heart?

Copyright © 2004 Lippincott Williams & Wilkins The Pulse Ventricular contraction Wave of increased pressure Begins at heart and travels to arteries Influenced by various factors Body size Gender Age Muscular activity Emotion Body temperature Thyroid secretion

Copyright © 2004 Lippincott Williams & Wilkins Checkpoint 15-16: What is the definition of pulse?

Copyright © 2004 Lippincott Williams & Wilkins Blood Pressure Force exerted by blood against vessel walls Determined by heart’s output and resistance to blood flow

Copyright © 2004 Lippincott Williams & Wilkins Cardiac Output Volume of blood pumped out of each ventricle in one minute Heart rate Beats per minute Stroke volume Controlled by force of contractions

Copyright © 2004 Lippincott Williams & Wilkins Resistance to Blood Flow Peripheral resistance is affected by Vasomotor changes Elasticity of blood vessels Viscosity Total blood volume

Copyright © 2004 Lippincott Williams & Wilkins Measurement of Blood Pressure Pressure is measured in the brachial arm artery using a sphygmomanometer Systolic pressure Occurs during heart contraction Diastolic pressure Occurs during heart relaxation

Copyright © 2004 Lippincott Williams & Wilkins Checkpoint 15-17: What is the definition of blood pressure? Checkpoint 15-18: What two components of blood pressure are measured?

Copyright © 2004 Lippincott Williams & Wilkins Abnormal Blood Pressure Hypotension Lower than normal blood pressure Hypertension High blood pressure Essential hypertension No apparent medical cause

Copyright © 2004 Lippincott Williams & Wilkins Treatment of Hypertension Stage 1 140/90 mm Hg Diet, exercise, weight loss Stage 2 160/100 mm Hg Drugs added to treatment

Copyright © 2004 Lippincott Williams & Wilkins Checkpoint 15-19: What is meant by hypertension and hypotension?

Copyright © 2004 Lippincott Williams & Wilkins Arterial Degeneration and Other Blood Vessel Disorders Arteriosclerosis Atherosclerosis Clot formation Leg cramps, pain, lameness Cerebral artery sclerosis Hypertension Coronary artery arteriosclerosis Renal artery damage Ischemia

Copyright © 2004 Lippincott Williams & Wilkins Treatment for Arterial Degeneration Balloon catheterization Bypass grafts Stents Endarterectomy

Copyright © 2004 Lippincott Williams & Wilkins Aneurysm Bulging sac in blood vessel wall Swelling deranges other structures Can burst, causing death Surgery can replace damaged segment

Copyright © 2004 Lippincott Williams & Wilkins Hemorrhage Profuse escape of blood from vessels Internal or external Can be life-threatening Apply pressure to wound Elevate extremity above heart Apply pressure to pressure point

Copyright © 2004 Lippincott Williams & Wilkins Shock Inadequate blood flow to tissues Classified by type Cardiogenic Septic Hypovolemic Anaphylactic Classified by severity (cause unknown) Mild Severe

Copyright © 2004 Lippincott Williams & Wilkins Checkpoint 15-20: With regard to the circulation, what is meant by shock?

Copyright © 2004 Lippincott Williams & Wilkins Thrombosis Formation of blood clot in a vessel Deep venous thrombosis (DVT) Embolus Pulmonary embolism Phlebitis Thrombophlebitis

Copyright © 2004 Lippincott Williams & Wilkins Varicose Veins Superficial veins that are swollen, distorted, and ineffective Saphenous veins of lower extremities Rectal veins (hemorrhoids)