ANA Lab Media and Blood

Flashcard reviewer for Mediastinum and Blood along with its parts for Anaphy Lab practicals and quiz

What is the mediastinum?

A movable partition that extends superiorly to the thoracic outlet and the root of the neck and inferiorly to the diaphragm.  

Where does the mediastinum extend anteriorly and posteriorly?

Anteriorly to the sternum and posteriorly to the vertebral column.  

What does the mediastinum contain?

The remains of the thymus, the heart and large blood vessels, the trachea and esophagus, the thoracic duct and lymph nodes, the vagus and phrenic nerves, and the sympathetic trunks.  

What are the divisions of the mediastinum?

Superior Mediastinum and Inferior Mediastinum.  

What is the function of the diaphragm?

A thin muscular and tendinous septum that's very important to respiration.  

What are the three parts of the origin of the diaphragm?

Sternal part, Costal part, Lumbar part.  

How is the diaphragm secured to the thoracic cage?

Left & Right Crus, Central tendon, Arcuate ligament.  

What are the openings of the diaphragm and their vertebral landmarks?

• Aortic hiatus (T12)

• Esophageal hiatus (T10)

• Caval hiatus (T8)

What passes through the aortic hiatus?

Aorta, thoracic duct, azygous vein.  

What passes through the esophageal hiatus?

Esophagus, vagal nerve, esophageal branches of the gastric vessels, some lymphatic vessels.  

What passes through the caval hiatus?

Inferior vena cava, right phrenic nerve.  

What is the nerve supply of the diaphragm?

Phrenic nerve (C3,4,5).  

What is the motor and sensory nerve supply of the diaphragm?

Motor: C3,4,5 Right and Left phrenic nerve

Sensory: Phrenic nerve (central) and Lower 6 intercostal nerves (peripheral).

What is the blood supply of the diaphragm?

Pericardiophrenic and Musculophrenic artery and vein, Superior phrenic artery and vein, Inferior phrenic artery and vein.  

What is the pleura?

Serous membrane that folds back on itself to form a 2-layered membranous pleural sac.  

What are the parts of the pleura?

Parietal layer and visceral layer.  

What does the parietal layer of pleura line?

The thoracic wall, covers the thoracic surface of the diaphragm and extends into the root of the neck to line the undersurface of the suprapleural membrane at the thoracic outlet.  

What does the visceral layer of pleura cover?

The outer surfaces of the lungs and extends into the depths of the interlobar fissures.  

What separates the parietal and visceral layers of pleura?

The pleural cavity or pleural space.  

What does the pleural cavity contain?

A small amount of tissue fluid, the pleural fluid.  

What is the function of the pleural fluid?

Covers the surfaces of the pleura as a thin film and permits the two layers to move on each other with the minimum of friction.  

What is the length and diameter of the trachea?

About 4 ½ inches or 11.25 cm long and 2.5 cm in diameter.  

Where does the trachea begin?

• Begins in the neck as a continuation of the larynx at the lower border of the cricoid cartilage at the level of C6.  

Where does the trachea end?

• Ends below at the carina by dividing into right and left principal bronchi at the level of the sternal angle.  

What keeps the trachea patent?

The presence of U-shaped bars (rings) of hyaline cartilage embedded in its wall.  

What is the blood supply of the trachea?

Upper 2/3 supplied by the inferior thyroid artery and vein.  

Lower 1/3 supplied by the bronchial arteries and vein.

What is the nerve supply of the trachea?

Sensory nerve supply: from vagi and recurrent laryngeal nerves.  

Sympathetic nerve supply to the trachealis muscle.

What does the trachea bifurcate into?

Right and left principal (primary or main) bronchi.  

Where does the trachea bifurcate?

Behind the arch of the aorta.  

How does the right principal bronchus differ from the left?

Right: Wider, shorter, and more vertical; 2.5 cm or 1 inch long; Gives off the superior lobar bronchus before entering the hilum; Divides into middle and inferior bronchus upon entering the hilum.  

Left: Narrower, longer, and more horizontal; 5 cm or 2 inches long; Passes to the left below the arch of the aorta and in front of the esophagus; Divides into superior and inferior lobar bronchus upon entering the hilum.

Describe the lungs.

Soft, spongy, and very elastic; conical, covered with visceral pleura, and suspended free in its own pleural cavity, being attached to the mediastinum only by its root.  

What are the parts of the lungs?

• A blunt apex, which projects upward into the neck.  

• A concave base that sits on the diaphragm.  

• A convex costal surface, which corresponds to the concave chest wall.  

• A concave mediastinal surface, which is molded to the pericardium and other mediastinal structures.

What is the hilum of the lung?

A depression in the middle of the mediastinal surface where the bronchi, vessels, and nerves that form the root enter and leave the lung.  

How is the right lung divided?

By oblique and horizontal fissures into 3 lobes: Upper, Middle, and Lower Lobes.  

How is the left lung divided?

By the oblique fissure into 2 lobes: Upper and Lower Lobes.  

What is the blood supply of the lungs?

• Bronchial arteries (branches of the Descending Aorta).  

• Bronchial veins (drains into the azygous and hemiazygous veins).  

• Pulmonary arteries (supply deoxygenated blood to the alveoli).  

• Pulmonary veins (carry oxygenated blood from the alveolar capillaries).

What is the nerve supply of the lungs?

Pulmonary plexus composed of efferent and afferent autonomic nerve fibers. The plexus is composed of sympathetic and parasympathetic fibers from the vagus nerves.  

What is the pericardium?

A fibroserous sac that encloses the heart and the roots of the great vessels.  

What is the function of the pericardium?

To restrict excessive movements of the heart as a whole and to serve as a lubricated container in which the different parts of the heart can contract.  

Where is the pericardium located?

Within the middle mediastinum.  

What is the nerve supply of the fibrous pericardium and the parietal layer of the serous pericardium?

Phrenic nerves.  

What is the nerve supply of the visceral layer of the serous pericardium?

Branches of the sympathetic trunks and the vagus nerves.  

Describe the heart.

A hollow muscular organ that is somewhat pyramid-shaped and lies within the pericardium in the mediastinum. It is connected at its base to the great blood vessels but otherwise lies free within the pericardium.  

What are the surfaces of the heart?

• Sternocostal (anterior)

• Diaphragmatic (inferior)

• Base (posterior)

What are the borders of the heart?

• Right border: Right Atrium

• Left border: Left auricle

What are the chambers of the heart?

Right Atrium, Right Ventricle, Left Atrium, Left Ventricle.  

What is the sulcus terminalis?

A vertical groove that serves as the junction between the right atrium and right auricle.  

What is the crista terminalis?

Ridges inside the heart.  

What are the openings in the right atrium?

Superior and Inferior vena cava, Coronary sinus, Right atrioventricular orifice.  

What is the sinoatrial (SA) node?

Located in the right atrium and is the pacemaker of the heart.  

What are the trabeculae carneae?

Projecting ridges on the ventricular walls that have a spongelike appearance.  

What are papillary muscles?

Project inwards, attached by their bases to the ventricular wall, and connected by chordae tendineae.  

What is the moderator band?

Crosses the ventricular cavity from the septal to anterior wall.  

What is the tricuspid valve?

Guards the atrioventricular orifice and consists of 3 cusps.  

What is the pulmonary valve?

Guards the pulmonary orifice and consists of 3 semilunar cusps.  

Where is the left atrium situated?

Behind the right atrium and forms the great part of the base of the posterior surface.  

What are the openings in the left atrium?

4 pulmonary veins (no valves).  

How does the left ventricle differ from the right ventricle?

The left ventricle is 3x thicker than the right ventricle.  

What is the mitral valve?

Guards the atrioventricular orifice and consists of 2 cusps.  

What is the aortic valve?

Guards the aortic orifice.  

What is the blood supply of the heart?

Right and Left Coronary Artery.  

Where do the coronary arteries originate?

Ascending Aorta.  

Describe the right coronary artery.

Arises from the anterior aortic sinus of ascending aorta and runs forward between the pulmonary trunk and right auricle.  

Describe the left coronary artery.

Usually larger than the right coronary, supplies the major part of the heart.  

Name the branches of the right coronary artery.

Right conus artery, Anterior ventricular branches, Posterior ventricular branches, Posterior interventricular (descending) artery, Atrial branches.  

Name the branches of the left coronary artery.

Anterior interventricular (descending) branch, Circumflex artery.  

What are the veins that drain the heart?

Great cardiac vein, Small and Middle cardiac vein, Anterior cardiac vein.  

Where does most of the blood from the heart drain?

Right atrium through the coronary sinus.  

Where does the coronary sinus open?

Right atrium to the left of the inferior vena cava.  

What is the nerve supply of the heart?

Cardiac Plexuses (Sympathetic and parasympathetic fibers of the autonomic nervous system).  

Where are the cardiac plexuses situated?

Below the arch of the aorta.  

Where is the tricuspid valve located?

Behind the right half of the sternum opposite the 4th intercostal space.  

Where is the mitral valve located?

Behind the left half of the sternum opposite the 4th costal cartilage.  

Where is the pulmonary valve located?

Behind the medial end of the third left costal cartilage and the adjoining part of the sternum.  

Where is the aortic valve located?

Behind the left half of the sternum opposite the 3rd intercostal space.  

How is the right brachiocephalic vein formed?

At the root of the neck by the union of the right subclavian and right internal jugular vein.  

How is the left brachiocephalic vein formed?

Has a similar origin to the right brachiocephalic vein.  

What does the superior vena cava contain?

All the venous blood from the head and neck and both upper limbs.  

How is the superior vena cava formed?

By the union of the 2 brachiocephalic veins.  

What veins make up the azygous system?

The main azygous vein, inferior hemiazygos vein, and superior hemiazygos vein.  

Where does the inferior vena cava pierce the diaphragm?

The central tendon of the diaphragm opposite the eighth thoracic vertebra.  

Where do the pulmonary veins carry blood from?

Leave each lung carrying oxygenated blood.  

What is the aorta?

The main arterial trunk that delivers oxygenated blood from the left ventricle of the heart to the tissues of the body.  

Where does the ascending aorta begin and run?

Begins at the base of the left ventricle and runs upward and forward to come to lie behind the right half of the sternum.  

What are the branches of the ascending aorta?

Left and Right Coronary arteries.  

Where does the arch of the aorta lie?

Behind the manubrium sterni and arches upward, backward, and to the left in front of the trachea.  

What are the branches of the arch of the aorta?

Brachiocephalic artery, left common carotid, left subclavian.  

Where does the descending thoracic aorta lie?

In the posterior mediastinum.  

Where does the descending thoracic aorta begin?

As a continuation of the arch of the aorta on the left side of the lower border of the body of the 4th thoracic vertebra.  

What are the branches of the descending thoracic aorta?

Posterior intercostal arteries, pericardial, esophageal, and bronchial arteries.  

What does the pulmonary trunk convey?

Deoxygenated blood from the right ventricle of the heart to the lungs.  

Where does the pulmonary trunk leave?

The upper part of the right ventricle.  

What does the pulmonary trunk divide into?

Right and left pulmonary artery.  

What type of tissue is blood?

A type of connective tissue that has a liquid matrix filled with cells & cell fragments.  

What are the functions of blood?

Transport of substances, Regulates pH, Maintain body temperature, protection against foreign substances, clotting.  

What regulates blood?

Colony-stimulating factors and hormones (ex. EPO).  

Describe red blood cells (RBCs).

Specialized, anucleated, biconcave disks.  

What are the components of RBCs?

Hemoglobin, Lipids, ATPS, Carbonic anhydrase.  

What is the main function of RBCs?

Transport O2 to tissues & CO2 to the lungs.