Heart Lab

Right ventricle

1 of 4 chambers; rough, muscular walls; muscle wall thicker than either atrium and thinner than left ventricle; Responsible for pumping oxygen poor blood to lungs.

Right atrium

1 of 4 chambers; smooth, thin, posterior wall; thin, rough anterior wall; receives superior and inferior venae cavae and coronary sinus

Left ventricle

1 of 4 chambers; thick muscular walls; separated from let atrium by left atrioventricular valve; walls twice as thick as right ventricle; forms apex; responsible for pumping oxygen-rich blood to body (except to lungs)

Function of Atria

Collect blood returning to the heart.

endocardium

"inside the heart" is a glistening white sheet of endothelium (squamous epithelium) resting on a thin connective tissue layer. Located on the inner myocardial surface, it lines the heart chambers and covers the fibrous skeleton of the valves.

Where is the endocardium found and what kind of tissue is it?

-The endocardium is the inner layer of the heart. It consists of epithelial tissue and connective tissue. -Lines the inner cavities of the heart, covers heart valves and is continuous with the inner lining of blood vessels. (the inner lining of vessels are endothelial cells) -Purkinje fibers are located in the endocardium. They participate in the contraction of the heart muscle.

pulmonary veins

4 veins: enter the left atrium; transport blood from the lungs back to the heart (best seen posteriorly)

Ascending aorta

Ascends short distance within the pericardium; Has aortic valve at its origin; origin: Left ventricle (aortic vestibule)

Superior vena cava

Drainage: Head, Upper limbs, etc.

Anterior interventricular sulcus

Groove on anterior surface; extends from coronary sulcus to inferior margin; marks position of interventricular septum;

Pulmonary Trunk

Origin: Right ventricle; Distributes to the lungs; pumps oxygen-poor blood from right ventricle; has the pulmonary valve at its origin.

Right coronary artery

Passes between pulmonary trunk and right auricle; lies in the coronary sulcus; distributes blood to the right atrium, right ventricle and left ventricle.

Purkinje fibers

Purkinje fibers (Purkyne tissue or Subendocardial branches) are located in the inner ventricular walls of the heart, just beneath the endocardium. These fibers are specialized myocardial fibers that conduct an electrical stimulus or impulse that enables the heart to contract in a coordinated fashion.

Coronary sulcus

Surface groove surrounding heart; marks junction between atria and ventricles

Where is the myocardium found and what kind of tissue is it?

The endocardium underlies the much more voluminous myocardium, the muscular tissue responsible for the contraction of the heart. Cardiac muscle is a type of involuntary striated muscle found in the walls and histologic foundation of the heart, specifically the myocardium.

Where is the pericardium found and what kind of tissue is it?

The pericardium (from the Greek περι, "around" and κάρδιον, "heart" /perikardion/) is a double-walled sac that contains the heart and the roots of the great vessels. There are two layers to the pericardial sac: the fibrous pericardium and the serous pericardium.

Left ventricle

ejects blood into the aorta (largest artery in the body)

What kind of tissue is endomysium, perimysium and epimysium and where is it located in the myocardium?

endo = individual cell connective tissue peri = larger groups of connective tissue surrounding cells. Starts at the smallest (one cell) being surrounded by endomysium, then groups of cells surrounded by perimysium, then the epimysium and so on.

cardi =

heart

right auricle

increase the atrial volume somewhat.

trabeculae carneae

irregular ridges of muscle that line the internal walls of the ventricular chambers.

systemic circuit pump

left side of the heart. takes a long pathway through the entire body and encounters about five times as much friction or resistance to blood flow than the pulmonary circuit pump.

myocardium

middle layer of the heart wall; composed mainly of cardiac muscle and forms the bulk of the heart; circular and spiral arrangement of cardiac muscle.

superficial epicardium

often infiltrated with fat (adipose), especially in older people. (visceral layer of the serous pericardium)

2 layers of te pericardium

parietal: lines the internal surface of the fibrous pericardium. attaches to the large arteries exiting the heart then turns inferiorly and continues over the external heart surface as the visceral layer.

Right ventricle

pumps blood into the pulmonary truck, which routes the blood to the lungs where gas exchange occurs.

inferior vena cava

returns blood from body regions inferior to the diaphragm. (lack oxygen.

superior vena cava

returns blood from body regions superior to the diaphragm. (lack oxygen)

left coronary artery

runs toward the left side of the heart and then divides into its major branches.

circumflex artery

supplies the left atrium and the posterior walls of the left ventricle.

pericardium

the double walled sac surrounding the heart.

coronary circulation

the functional blood supply of the heart, is the shortest circulation in the body.

fossa ovalis

the interatrial septum's shallow depression. it marks the spot where an opening, the foramen ovale, existed in the fetal heart.

interatrial septum

the internal partition that divides the heart longitudinally at the atria

interventricular septum

the internal partition that divides the heart longitudinally at the ventricles.

Mediastinum

the medial cavity of the thorax where the heart resides.

pulmonary circuit pump

the right side of the heart. short, low-pressure circulation.

Function of Ventricles

to pump blood from the heart.

fibrous pericardium

tough, dense connective tissue layer protects the heart, anchors it to surrounding structures, and prevents overfilling of the heart with blood.

ventr =

underside

also called the epicardium

visceral layer of the serous pericardium

pectin =

comb

coronary sinus

collects blood draining from the myocardium

papillary muscles

conelike, play a role in valve function, project into the ventricular cavity.

fibrous skeleton of the heart

connective tissue fibers that form a dense network to reinforce the myocardium internally and anchor the cardiac muscle fibers.

corona =

crown

serous pericardium

deep to the fibrous pericardium: a thin, slippery, 2-layer serous membrane. its parietal layer lines the internal surface of the fibrous pericardium.

anterior interventricular artery

also known clinically as the left anterior descending artery: follows the anterior interventricular sulcus and supplies blood to the interventricular septum and anterior walls of both ventricles;

peri =

around

pectinate muscles

bundles of muscle that look like the teeth of a comb inside of the anterior portion of the right atrium.