Ch 20 Intro To Heart Anatomy Flashcards
Heart generates
BP
Heart routes
Blood
Heart separates these 2 circulations
Pulmonary and systemic
Heart ensures ____ way blood flow
One
Heart____ ensure one way blood flow
Valves
The heart regulates blood supply
Changes in contraction rate and force match blood delivery to changing metabolic needs
The heart pumps _____ blood to the tissues and ______ blood to the lungs
Oxygenated
Deoxygenated
When you inhale you add____ to the blood. When you exhale you remove ____ from the blood
Oxygen
Carbon dioxide
Systemic circulatory system
Contains blood vessels from limbs, head and neck, organs
Pulmonary circuit
Oxygenating and deoxygenated blood
Unidirectional flow
One way blood flow
Where is the heart located
Thoracic cavity, mediastinum
Mediastinum
Lies between right and left pleurae
Extends from sternum in front to vetebral column behind
Contains all the thoracic viscera excepting the lungs
Divisions of mediastinum
2 divisions
Superior and
inferior- which can be again divided into anterior, middle and posterior
Most structures of heart are in the
Superior or middle of inferior
Superior mediastinum contents
Blood vessels;
Veins: SVC, L and R brachiocephalic veins
Arteries: arch of aorta, brachiocephalic artery, L common carotid, L subclavian artery
Middle mediastinum contents
Heart with pericardium Ascending Aorta Bifurcation of trachea Pulmonary trunk and divisions Lower half of SVC R and L pulmonary veins Pherenic nerve Deep cardiac plexus
All vessels that go in and out the heart are included in the ____
Middle mediastinum
Levels of organization
Chemicals to cells to tissues to organs to systems
Tissue make up of heart
Fibrous pericardium
Myocardium -cardiac muscle
Endocardium
Pericardium is same as epicardium here no distinguish needed
Visceral layer , serous membrane
Function: restrict excessive movement of the heart as a whole and to serve as a lubricated container in which different parts of the heart can contract
Glove around heart
Cells secrete - pericardial fluid, coats outer surface of heart
2 components- pariteal and visceral
Myocardium
Cardiac muscle layer forming the bulk of the heart
Work horse, thickest section
Tissue of the heart that contracts, needs ATP- myocardial infarction, heart attack
Function: provide scaffolding to chambers, assist in contraction and relaxation of cardiac walls so blood can pass between chambers, conducting electro- stimulation through its own tissue and into epicardium
Endocardium
(Squamous )Endothelial layer of the under myocardial surface
Internal layer
Conducting system of the heart
Set of spaces/chambers
Secretes anticoagulants inside spaces of heart, minimizes blood clotting
Protects myocardium underneath, shields from chemicals
____ line cavities open to outside world
Mucous membranes- respiratory, digestive, urinate tract, reproductive
Serous membrane
Membranes not open to outside world Mediastinum
Average heart rate
75 beats/ minute
Cardiomyocytes ( found in mycardium)
Contractile cells of the heart- what die during a heart attack
____ of the myocardium determines the strength of the hearts ability to pump blood
The thickness
When platelets rupture they release
Clotting factors
External structures
Apex- bottom
Base- top bottom of great structures
Apex
Directed downward , forward and to the left and is overlapped by the left lung and pleura
Function of the apex is
To pump blood to left atriumr
Auricle
Roof of internal chambers, atria
Grooves on surface of heart
Anterior interventricular sulcus
Coronary sulcus
Runs along right side
Interior has 4 chambers (space)
Left ( atrial) - left atrium, left ventricle
Right( venous)- right atrium, right ventricle
Right atrium - receiving chamber
Received deoxygenated blood from the body through the superior vena cava ( head and upper) and inferior vena cava ( leg and lower torso)
Left atrium- receiving chamber
Receives oxygenated blood from the lungs through the pulmonary vein
Right chambers shaded blue because
They carry deoxygenated blood
Red shading means
Oxygenated blood, high in oxygen
Atria function as
Primer pumps thst increase ventricular pumping effectiveness 20%
Atria increase ventricular pumping 20 % by…
Blood flows from great vein to atria (80% directly to ventricles before the atria contract) atrial contract (additional 20% filing of ventricles)
Lower chambers of the heart ( discharge chambers)
Ventricles
Function of ventricles
Blood moves from ventricles out of the heart
Thicker muscle wall
L- pumps blood around body, thicker
R- pumps blood to lungs
Septum’s
2
Interventricular Septum- IVS
Between ventricles - separates 2 lower chambers
Interatrial septum
In between atria seperates upper chambers
The heart has how many sets of valves
4
Valves allow the heart to pump blood in a
Uni- directional format
Valves are located
Within the chambersy
Blood flow is always ____ within valves
Uni directional through chambers from the heart to the body
Pulmonary and aortic valve job is to
Moving blood forces valve open , when valves close back flow of blood stops
Bicuspid and tricuspid valve job
Valves open allowing blood from atria to fill ventricles, when ventricles contract these help to prevent back flow
Valves allow blood flows
From atria to ventricles but not from ventricle back to atria
Papillary muscles
Chords tendinae attach, closing moment of valves
Papillary muscles control
Closing movement
Cardiac conduction system
Cardiac muscle can generate its own electrical current (automacity)
The state of a hearts electrical functioning can be measured and evaluated on a
Electrocardiogram- ECG
Dysrythmia
Interrupts rhythmical contraction of the heart
The heart doesn’t need what system to contract
Nervous system, discharge on their own
1 sinoatrial SA node
Pace maker-
2 atrioventricular AV node
Acts like an antenna- picks up electrical current and directs movement into lower aspect of heart
- Atrioventricular AV bundle- bundle of HIS
Conducts current from AV node into atriventricular septum
Divides into the 2 ventricles-
- Right and left bundle branch
Go to respective ventricles
- Purkinje fibers
Attach to myocardicytes, myocardium will contract
Cardiac excitation, contraction coupling
1 sinovial node
- Atriventricular node
- Atrioventricular bundle ( bundle of his)
- Right and left bundle branches
- Purkinje fibers
EKG is a series of a
Electrical activity
EKG tell us
P wave- electrical activity in atria- depolarization and contraction- atria disorder
QRS-complex- depolarization of ventricular myocardium- downward, upward, downward- ventricular contraction disorder
T wave- repolarization of ventricular myocardium- resting- ventricular relaxation disorder
