The Heart (Q3,P2) Flashcards
Atria
- Upper chambers of the heart
- Receive blood from the pulmonary and systemic circuits
Ventricles
- Lower chambers of the heart
- the pumping chambers of the heart for both the pulmonary and systemic circuits
Veins
- Carries low O2 blood back to heart
- blood vessels that carry blood that is low in oxygen from the body back to the heart for reoxygenation.
Arteries
- Carries O2 blood from heart to the body
- blood vessels that carry oxygen-rich blood away from the heart to the body.
Pulmonary Circuit
takes blood to and from the lungs
Systemic Circuit
vessels transport blood to and from body tissues
Location of the Heart
- Weights under a pound
- Largest organ of the mediastinum (organs in thoracic cavity)
- Located between the lungs
Layers of the Pericardium
- Fibrous Pericardium
Serous Pericardium: 2. Parietal 3. Visceral
Fibrous Pericardium
- strong layer of dense connective tissue (forms one of the three layers)
- external layer of the pericardium
Parietal Pericardium
Outer layer of the serous pericardium
Visceral Pericardium
- Inner layer of the serous pericardium
- Also forms the Epicardium
Layers of the Heart Wall
- Epicardium
- Myocardium
- Endocardium
Epicardium
Layer of heart wall
the external layer of the heart wall and is also the visceral layer of the serous pericardium
Myocardium
- Layer of heart wall
- consists of cardiac muscle (middle layer of the heart wall)
Muscle arranged in circular and spiral patterns
Endocardium
Layer of the heart wall
– endothelium resting on a layer of connective tissue – inner layer of the heart wall
Lines the internal walls of the heart and forms the heart valves
What are heart chambers?
Internal divisions of the atria and ventricles
Interventricular and interatrial septa
Coronary sulcus
an external groove that marks the division between the atria and the ventricles
Anterior and posterior interventricular sulcus
external grooves that mark the division between the ventricles on the both the anterior and posterior side of the heart
Right Atrium
- End of the Systemic Circuit
(low O2 blood has cycled around the body and comes back for more O2) - Receiving chamber for oxygen poor blood
- Vessels coming into this chamber include the Superior Vena Cava, Inferior Vena Cava, Coronary Sinus
Superior Vena Cava
- opening/orifice found in Right Atrium
- Receives oxygen-poor blood draining superior to the diaphragm
Inferior Vena Cava
- opening/orifice found in Right Atrium
- Receives oxygen-poor blood draining inferior to the diaphragm
Coronary Sinus
- opening/orifice found in Right Atrium
- Receives oxygen-poor blood draining from the walls of the heart
- located on the posterior portion or the coronary sulcus (seen on the back of the heart)
drains the oxygen poor blood from the tissues of the heart itself and empties into the right atrium
Fossa ovalis
remnant of a fetal circulatory structure known as the foramen oval
- part of the interatrial septum
- Part of the Right Atrium
Tricuspid valve
- Part of the Right Atrium
- is located between the right atrium and right ventricle (also called: Right AV (atrioventricular) valve)
When this valve opens blood flows from the right atrium to the right ventricle
When this valve closes, it prevents back-flow from the right ventricle to the right atrium
Right Ventricle
Start of the Pulmonary Circuit
Pumping chamber for the pulmonary circuit – oxygen poor blood is pumped from the heart back to the lungs
Pulmonary Trunk
Vessel that leaves the right ventricle
(opening/orifice for this vessel is found in the RV)
Papillary Muscles
cone-shaped muscles projecting from the ventricular wall
(Anchors for the chordate tendineae)
- Part of the Right Ventricle
Chordae Tendineae
- Part of the Right Ventricle
- thin strong bands attached to the papillary muscles and the flaps of the tricuspid valve; help to prevent back-flow of blood from the right ventricle into the right atrium
Pulmonary valve (also called: pulmonary semilunar valve)
the valve located at the base of the pulmonary trunk
When this valve opens blood flows from the right ventricle to the pulmonary trunk
When the valve closes it prevents back-flow from the pulmonary trunk back into the right ventricle
Left Atrium (LA)
- End of the pulmonary circuit
- Receiving chamber for oxygen-rich blood
- Vessels coming into this chamber: Two right pulmonary veins, Two Left Pulmonary Veins
Two Right Pulmonary Veins
(opening/orifice found in LA)
Receives oxygen-rich blood returning from the right lung
Two Left Pulmonary Veins
(opening/orifice found in LA)
Receives oxygen-rich blood returning from the left lung
Remember! Bi is left, tri is right
Left Ventricle (LV)
- Start of Systemic Circuit
- Pumping chamber for the systemic circuit
Vessel leaving this chamber is called the aorta - Three times thicker than the right ventricle
- Exerts more pumping force than RV
Flattens the RV into a crescent shape
Aorta
(opening/orifice for this vessel is found in the Left Ventricle
Bicuspid valve
is located between the left atrium and left ventricle (Also called: Left AV (atrioventricular) valve; mitral valve)
When this valve opens blood flows from the left atrium to the left ventricle
When this valve closes, it prevents back-flow from the left ventricle to the left atrium
Papillary muscles (LV)
cone-shaped muscles projecting from the ventricular wall
Chordae tendineae (LV)
thin strong bands attached to the papillary muscles and the flaps of the bicuspid valve; help to prevent back-flow of blood from the left ventricle into the left atrium
Aortic valve (Also called: aortic semilunar valve
the valve located at the base of the aorta
When this valve opens blood flows from the left ventricle to the aorta
When the valve closes it prevents back-flow from the aorta back into the left ventricle
Cardiac Cycle
Each complete beat the heart makes
The heart makes 2 sounds: Lub (systole contraction, emptying) and Dub (diastole relaxation of ventricles, refilling)
Atria
Thin walls of the heart
Ventricles
Thick walls of the heart (to push blood further)
What is every heart valve composed of?
Endocardium with a connective tissue core
Atrioventricular (AV) valves
located between atria and ventricles
(Tricuspid and bicuspid valves)
Aortic and pulmonary valves
at junction of ventricles and great arteries
Conducting System of the Heart
- A series of specialized cardiac muscle cells that rhythmically generate and conduct impulses
- SINOATRIAL (SA) NODE sets the inherent rate of contraction – known as the heart’s internal pacemaker
Nerves to the Heart
- Visceral sensory fibers
- Parasympathetic branches of the vagus nerve
- Sympathetic fibers – from cervical and upper thoracic chain ganglia
- The nerves that receive external controls, that then alter heart rate
Coronary arteries
Supply oxygen-rich blood to the tissues of the heart
Arise (or branch) from the ascending aorta
Located in the coronary sulcus
2 Branches: Left and right coronary arteries
Heart Flow Diagram
