The parts concerned in the controlling and conducting mechanism of the heart are composed of myocardial tissue distinguished from the ordinary cardiac muscle, not only because it is less highly differentiated from the original cells, but also because the muscle fibres are intimately associated with numerous nerve cells and fibrils which probably have a share […]
The tissues that form the skeletal structure of the heart are four annular fibrous rings, two small bones, the muscle, serous membrane, vessels and nerves. Fibrous rings The fibrous rings are four in number-two at the atrio-ventricular openings and two at the arterial openings. The former separate the muscle fibres of the atria from those of
Horse The base is broader and the length from the base to apex is shorter. The long axis is more oblique. The anterior border is more strongly convex. It weighs about 2.9 kg to 3.1 kg. The intermediate groove is absent. Instead of os cordis, the aortic ring contains on the right side a plate
LEFT VENTRICLE OF HEART The left ventricle forms the left posterior part of the ventricular mass. It is more regularly conical and its wall is much thicker than the right ventricle. It forms the entire posterior contour of the heart and carries the apex of the heart. The base is continuous with the left atrium
LEFT ATRIUM OF HEART The left atrium forms the posterior part of the base of the heart. It lies behind the pulmonary artery and aorta and above the ventricle. It consists of a sinus and an auricle. The later extends on the left side and its blind end lies behind the origin of the pulmonary
RIGHT VENTRICLE OF HEART The right ventricle forms the anterior part of the ventricular mass and forms the anterior border of the heart. It does not reach the apex of the heart. It is triangular in outline and crescentric on cross section. It communicates above at the base with the right atrium through the right
RIGHT ATRIUM (RIGHT AURICLE) OF HEART The right atrium forms the right anterior part of the base and is above the right ventricle. It consists of a principal cavity called the sinus venarum and a blind diverticulum called the auricle or auricular appendix. The sinus venarum is the cavity into which the veins open. The
The four chambers are externally marked by the transverse grooves and longitudinal groove which are occupied by fat and coronary vessels. The heart is divided into four chambers- Right atrium Right Ventricle Left atrium Left ventricle
The pericardium is a fibro-serous sac which encloses the heart and in part, the great vessels entering and leaving the heart. It consists of two layers, fibrous and serous. The fibrous layer is thin but strong and inelastic. It is attached above to the great blood vessels at the base of the heart and below
Structure of Heart in animals The heart is an involuntary muscular organ which occupies the greater part of the middle mediastinal space. Its shape is an irregular and somewhat flattened cone. It is attached at the base by the great blood vessels but otherwise it is free in the pericardium. Structure of Heart is asymmetrical
