The Circulatory System

The Heart Chapter 20

Life without the circulatory system …… ???

Functions of the Cardiovascular System

1. Circulates Blood through the Body

2. Delivers Oxygen & Nutrients to Cells

3. Picks up CO2 & other Waste From Cells

4. Helps Maintain Homeostasis5. Helps Regulate Body

Temperature6. Helps maintain pH of Blood &

Body7. Helps fight infections8. Carries immunities for diseases

2 Circulatory Pathways :

1. Pulmonary Pathway To lungs with CO2

2. Systemic Pathway To the rest of the Body with

O2

Systemic Pathwayincludes…..

Coronary To heart via Coronary Arteries

Renal To Kidneys to be cleaned

Portal To digestive system to pick up nutrients

Hepatic To liver to store nutrients

Size & Location of the Heart Size:

12 cm long 9 cm wide 6 cm thick

Location: In Pericardial cavity in between lungs Area: Mediastinum – between two

pleural cavities 2/3 sits on the left side

Pericardium Double lining of the

pericardial cavity Visceral pericardium

Inner layer Parietal Pericardium

Outer layer Pericardial cavity

In between the parietal & visceral layers

Contains pericardial fluid

Pericardium

Wall Anatomy of the Heart 3 layers:

Epicardium Outer layer Part of the Visceral Pericardium Covers the heart

Myocardium Middle layer Muscular wall Concentric layer of cardiac muscle

tissue

Endocardium Inner layer Simple squamous epithelium

The 3 Layers of the Heart

External HeartLeft & Right AuricleLeft & Right Atrium

Left & Right Ventricle

ApexBase

Coronary VesselsArch of AortaPulmonary TruckVena Cava

Interventriclular Sulcus

Fat

External Heart (Anterior)

Myocardial Blood Flow

Superior Vena CavaRight Auricle /Right Atrium

Base of the Heart

Coronary Vessels

Interventriclular Sulcus

Apex of the Heart

Left Auricle/Left Atrium

Pulmonary Trunk

Pulmonary Artery

Arch of Aorta

External Heart (Posterior)

Pulmonary Artery

Pulmonary Vein

Apex

Arch of Aorta

Pulmonary Vein

Vena Cava