(4) Pulmonary pressure decreases forcing air into the lungs.
Extends from larynx to bronchi. Formed by smooth muscle, hyaline cartilage (C-shaped rings, prevents trachea from collapsing). Inner wall lined with ciliated mucosa. Functions as a air way passage for the lungs.
Divide into the left & right Bronchi at the carina. Composed of smooth muscle & cartilaginous rings. Inner wall composed with ciliated mucosa (composed of goblet cells). Goblet cells trap foreign particles, cilia pass particles into throat (to be expelled, prevents respiratory tract infection).
Explain the bronchial division;
(1) Bronchus enters lung, divides into secondary lobar branches.
(2) lobar branches divides into segmental bronchi, then dividing into bronchioles ending in alveolar duct & alveoli.
Composed of simple squamous epithelium. Exchanges O & CO2.
When does the bronchus and other structures enter the lung?
In the hilum.
Name the lobes of the left lung, and what are they separated by?
Superior & inferior lobe. Separated by fissure.
Name the lobes of the right lung, and what are they separated by?
Superior, middle, inferior, separated by the fissure.
Blood low in oxygen travels from?
Right ventricle--> left branch ofthe pulmonary artery -->left lung to be oxygenated.
Path way of oxygenated blood?
Leaves lungs through the pulmonary veins, then enters left atrium of heart.
What is the location of the heart?
Located within mediastinum, rest behind the sternum & on the diaphragm.
What is the pericardium for?
Protects the heart.
What is the Fibrous pericardium?
Outer layer of pericardium, fits loosely around heart & attaches to large blood vessels.
Name the substructures of the serous pericardium;
Parietal layer: Lines the inside of the fibrous pericardium.
Visceral layer: Attaches to the surface of the heart.
Pericardial space: Space between the two layers, contains pericardial fluid, acts as lubricant allowing heart to easily contract.
Name the layers of the heart, starting from the outer layer to the inner layer;
Epicardium: Outer layer of heart.
Myocardium: Muscle layer, helps contract and force blood from the hearts chambers.
Endocardium: Inner lining of the heart wall, lines all of the heart's chambers & valves, composed of endothelial tissue.
Name the four chamber of the heart:
Two atria (upper chambers)
Two ventricles (lower chambers)
Describe the atria:
Receives blood, has thinner walls, divided by the interatrial septum.
Describe the ventricles:
Pumps blood into arteries (leads away from heart), thicker myocardium, right ventricle pumps blood into lungs, left ventricle pumps blood into arteries that transports blood to all other regions of the body, divided by the interventricular septum.
Where is the atriventricular valve located?
Between each atrium & ventricle.
Where is the tricuspid valve located?
Between the right atrium & the right ventricle.
What happens when the B.P increases in the right atrium?
The tricuspid valves open, allowing blood to flow to the right ventricle.
What happens when the pressure in the right ventricle is greater than the pressure in the right atrium?
The bicuspid closes.
Describe the blood flow through the heart;
Deoxygenated blood enters --> Superior Vena Cava --> Right Atrium --> Tricuspid Valve --> Right Ventricle --> Semilunar Valve --> Pulmonary Artery --> Lungs --> blood is now oxygenated --> Left Atrium --> Mitral Valve --> Left Ventricle --> Aortic Semilunar Valve --> Aorta --> Rest of body
What two coronary arteries originate from the right coronary aorta?
The left & right coronary artery.
What artery branches to both ventricles?
Posterior descending artery.
What artery branches into the right ventricle and right atrium?
What artery supplies blood to both ventricles?
Anterior descending artery.
What artery supplies blood to the left ventricle & left atrium?
What is a cardiac cycle?
All actions that happen during a single heartbeat.
What is a systole?
The phase of contraction.
What is a diastole?
The phase of relaxation.
What is a atrial contract?
The forcing of blood into the ventricles.
The cardiac conduction system coordinates what?
The events of the cardiac cycle.
Where is the SA node located? What is it known as? And what is its function?
In the right atrial wall under the opening of the superior vena cava. The "pacemaker of the heart". To fire an electrical impulse that travels through the myocardium and stimulates the contraction in a rhythmic manner.
Where is the AV node located? Impulses from where travels down here? What does it provide? And why do action potential slows down here?
Located in the interatrial septum. Impulses from the SA node. It provides conduction pathway between atrium & ventricles. Because fibers are smaller.
What does the bundle of his connect?
The atria & ventricle.
What electrical impulses enters the purkinje fibers? And they spread impulses to what?
Bundle of His. The apex.
What are parasympathetic nerve fibers responsible for?
Slowing down the heart rate.
What does the sympathetic division secrete ( accelerates heart rate)?
What is the normal resting heart rate for an adult?
When does the heart begin to develop?
Before the end of the 3rd week.
What are the 5 specific regions of the primitive heart tube?