Physio - Cardiovascular System Flashcards
What are the 5 functions of the cardiovascular system
Circulate blood
Supply nutrition to cells
Remove metabolic waste to excretory organs
Transport hormones
Help regulate temperature
What are the lower chambers of the heart
Ventricles
What divides the left and right side of the heart
Septum
What are the upper chambers of the heart
Atriums
What are the 3 layers of cardiac tissue
Pericardium
Myocardium
Endocardium
What is the pericardium
A thin outer layer that surrounds the heart
What is the Myocardium
A thick layer of contractile tissue
What is the Endocardium
A thin inner layer that lines the chambers and valves of the heart
or
A thin inner layer which lines the inside of the heart
What are cardiomyocytes and a key feature
Cardiac muscle cells, contain many mitochondria
What are syncytium
A single cell containing multiple nuclei, created by the fusion of several cells
What are the gap junctions
Parts of intercalated discs that allow stimulation to transfer from one cell to another cell
What are desmosomes
Structures that hold cells together in contraction
Describe the flow of blood, starting from the pulmonary vein
O2: pulmonary vein, left atrium, left ventricle, aorta
CO2: vena cava, right atrium, right ventricle, pulmonary artery, lungs
What does the neural conduction system consist of
Sinoatrial node (SA)
Atrioventricular node (AV)
Atrioventricular bundle
Purkinje fibres
Describe the flow of the neural conduction system
SA node sends a signal to both atriums
The atriums contract
AV node sends a signal down the atrioventricular bundle and purkinje fibres
The ventricles contract
SA node sends another signal to both atriums to contract
Describe the sinoatrial node (SA)
A collection of specialised cells located on the right atrium
Where is the atrioventricular node (AV) located, and what does it do
Located in the atrioventricular septum
It delays the impulse by ~120 ms
What is the role of the atrioventricular bundle
It transmits the impulse from the AV node to the purkinje fibres
Describe the purkinje fibres
A network of specialized cells, abundant with glycogen.
It transmits the impulse to the cardiac muscles on the ventricles to contract
What establishes heart rate
The SA node, hormones, sympathetic and parasympathetic nervous systems
What are the sympathetic and parasympathetic nervous systems
Sympathetic NS is triggered during stress, increased HR
Parasympathetic NS is triggered during rest, decreased HR
What is systolic and diastolic pressure
Systolic pressure is the pressure exerted onto the arterial walls during a heartbeat
Diastolic pressure is the pressure exerted onto the arterial walls between heart beats
What is a normal value for systolic and diastolic pressure
Systolic: 90-120 mmHg
Diastolic: 60-80 mmHg
120/80 mmHg
What is the composition of air
78% Nitrogen
21% Oxygen
0.04% Carbon dioxide
0.06% other
Tachycardia refers to a heart beat over
100 bpm
On an ECG, what does the P wave represent
Atrial depolarisation
On an ECG, what does the QRS complex represent
Depolarisation of the ventricles
On an ECG, what does the T wave represent
Ventricular repolarisation
What are the main components of an ECG
P wave
QRS complex
T wave
