Term 3 - Blood Vessels Flashcards
Artery Layers and Their Features:
Inner Layer - Endothelium - one cell thick
Middle Layer - Smooth Muscle Fibre/Elastic Tissues - it rebounds, evens blood flow, is keeps blood at high pressure
Outer Layer Fibrous tissue - tough, creates resistant (doesn’t stretch)
What is an Arteriole?
A smaller version of the artery/ Branches out from artery/ connects artery to capillary
What is Vasoconstriction?
Smooth muscles in arteries constrict to decrease blood flow
e.g. - when you are cold, less heat is lost because arteries are further away from the skin
What is Vasodilation?
Smooth muscles in arteries relax to increase blood flow
e.g. when you are hot, more heat is lost because arteries are closer to the skin
What is the Lumen?
The lumen is the centre/cavity/hole in blood vessels that blood flows through.
Vein Layers and Their Features:
Inner Layer - Endothelium - one cell thick
Middle Layer - Smooth Muscle Fibre/Elastic Tissues - thinner layer of muscle than arteries, fewer elastic layers than arteries, blood at lower pressure
Outer Layer Fibrous tissue - gives strength and support
Valves - to stop back-flow
What are Smaller Veins Called?
Venules
What is the Difference in Size of Lumen between Veins and Arteries?
Veins have a larger lumen than arteries.
Capillary Features and Function:
Endothelium - one cell thick - allows for rapid diffusion
No muscle layer
No Fibrous Layer
Function: connect arteries/arterioles and veins/venules, exchange materials between the blood and cells, forms large networks called capillary beds
How Many Chambers of the Heart?
What are They?
4 - right ventricle, left ventricle, right atrium, left atrium
What is the Function of the Vena Cava?
Brings blood from the body into the heart
What is the Function of the Pulmonary Artery?
Pumps blood from the heart to the lungs
Name the Artery that Pumps blood from the Heart into the Body
Aorta
Name the Vein that brings blood from the Lungs to the Heart
Pulmonary Vein
