Circulatory system Flashcards
What is the circulatory system made up of?
Cardiovascular system and lymphatic system
What is the cardiovascular system made up of?
Arteriole system, the heart and the venous system
What is the lymphatic system made up of?
Lymphatic vessels and lymph nodes
What are the 4 functions of the circulatory system?
Distribution of gases and other molecules for nutrition, growth and repair
Chemical signalling (hormones)
Thermoregulation
Mediate inflammation and host defence responses
Describe the muscular double pump
Systole (contraction)
Diastole (relaxation)
Describe pulmonary circulation
From right side of heart to lungs to left side of heart
Describe systemic circulation
Left side of heart to capillary beds of organs and tissues to right side of heart
What are the 3 layers of the heart?
Epicardium, myocardium and endocardium
Describe the epicardium layer of heart
Visceral serous pericardium - external layer
Describe the myocardium layer of the heart
Cardiac muscle layer - middle layer
Describe the endocardium layer of the heart
Continuous with endothelial of blood vessels connecting with the heart - inner layer
Name the 4 cardiac valves
Pulmonary valve
Tricuspid valve
Mitral (bicuspid) valve
Aortic valve
Where is the pulmonary valve located?
Between the right ventricle and pulmonary trunk
Where is the tricuspid valve located?
Between the right atrium and right ventricle
Where is the mitral (bicuspid) valve located?
Between the right ventricle and pulmonary trunk
Where is the aortic valve located?
Between the left ventricle and the aorta
Blood leaving the left ventricle goes into what valve?
Aortic
Blood leaving right ventricle goes into what valve?
Pulmonary
What are the 3 layers of a blood vessel?
Tunica intima
Tunica media
Tunica adventitia
What is the tunica intima?
Internal layer - endothelium
What is the tunica media?
Middle layer - smooth muscle and connective tissue
What is tunica adventitia?
External layer - connective tissue
What is sympathetic tone?
Background, low level contraction of smooth muscle in arterioles
Production of action potentials to arterioles by sympathetic nerves causes what?
Sympathetic tone
What is vasodilation?
Relaxation of smooth muscles and widening of lumen - increases blood flow
What is vasoconstriction?
Contraction of smooth muscle and narrowing of lumen - reduces blood flow
What are anastosomes?
Where arteries connect to each other without and intervening capillary network
What is the role of anastosomes?
To provide alternative routes for blood flow to supply cells distal to an arterial occlusion
What is the name given to each alternative route given by anatosomes?
A collateral
What is an end artery?
The only arterial blood supply to a given area of the body
What is infarction?
Irreversible cell death due to hypoxia caused by loss of arterial blood supply
What does ascending aorta have?
Left and right coronary arteries
Where does an ascending aorta supply blood to?
Heart muscle
What does the arch of the aorta have?
Branches
Where does the arch of the aorta supply blood to?
Upper limbs and head
Where does the thoracic aorta supply blood to?
Thorax and abdomen
What does the abdominal aorta branch into?
Two common iliac arteries
Where does the abdominal aorta supply blood to?
Pelvis and lower limbs
What is blood pumped back towards the heart by?
Venous valves
Skeletal muscle pump
Accompanying veins
What system drains venous blood from absorpative parts of GI tract and associated organs to liver for cleaning?
Hepatic portal venous system
What system drains venous blood from all the organs and tissues into the superior and inferior vena cava?
Systemic venous system
What system drains venous blood from all the organs and tissues into the superior and inferior vena cava?
Systemic venous system
What system drains venous blood from all the organs and tissues into the superior and inferior vena cava?
Systemic venous system
What is lymph?
Interstitial fluid in the lymphatic vessels
