CIRCULATORY SYSTEM PT 1 - HEART Flashcards
Describe the size/positioning/inferior attachment of the Heart.
- Size of a fist
- Middle of the mediastinum with 2/3rds of mass on the left
- Attached to diaphragm inferiorly
The inferior portion of the heart is called?
Apex
The superior portion of the heart is called?
Base
Define Mediastinum.
Mass of organs between Lungs
Name the structures that border the Mediastinum.
Superior: 1st rib
Inferior: Diaphragm
Anterior: Sternum
Posterior: Vertebrae
What are the structures that make up the Mediastinum?
Trachea
Esophagus
Thymus/Lymph Nodes
Heart
What is Pericardium? Name the layers.
A two-layered CT membrane surrounding Heart
Fibrous and Serous
Describe Fibrous Pericardium.
A inelastic, dense irregular CT holding Heart in place and allows movement
Describe Serous Pericardium.
Deep to Fibrous, forming a double layer around Heart
Describe the Parietal Layer of the Serous Pericardium.
Outer layer fused to Fibrous Pericardium
Describe the Visceral Layer of the Serous Pericardium.
aka. Epicardium
Inner layer attached to Heart muscle
What is the Pericardial Cavity?
Space between the Parietal and Visceral layer filled with pericardial fluid to reduce friction
Name the layers that make up the Hearts walls. From superficial to deep.
Epicardium
Myocardium
Endocardium
Describe the Epicardium layer.
aka. Visceral layer of Serous Pericardium
Outer layer of simple squamous epithelium and CT with a smooth, slippery texture
Describe the Myocardium layer.
Cardiac muscle tissue - site of contractions
Describe the Endocardium layer.
Deep layer providing a smooth lining for chambers and valves
Describe Endothelium.
Simple squamous epithelium lining cavities of heart, blood and lymph vessels. Found in Endocardium layer
What is a Septa?
Dividing walls in heart
What does the Interatrial Septum divide?
Divides 2 Atria
What does the Interventricular Septum divide?
Divides 2 ventricles
What is the function of Veins?
Carry blood towards Heart
What is the function of Arteries?
Carry blood away from Heart
Explain the blood flow function of the Right Atrium.
- Receives blood from 3 veins
- Exits through the Tricuspid Valve (Right A-V Valve)
- Into the Right Ventricle