The thymus varies in size and development with the age of the individuals. Thymus begins to decrease in size and undergone involution with advancing age and gets gradually replaced by fat and connective tissue. The thymus is covered by a connective tissue capsule, which gives off numerous septa, which divide the gland into a number […]

Spleen has a capsule of connective tissue rich in elastic tissue and smooth muscle, over the capsule is serosa. Trabeculae from the capsule extend into the interior and form complicated framework by anastomoses. The spaces within the connective tissue framework are filled with a soft sponge like tissue known as splenic pulp. On the basis of

Lymph gland Lymph nodes (Lymph gland) occur in the of lymphatics of lymph vessels. Lymph flows through them. These vary in size form those just visible to naked eye to those several centimeters in diameter. They are flattened and been-shaped with a definite hilum. They have a connective tissue capsule containing a few elastic and

The palatine tonsil is an egg-shaped mass, which bulges into the oral cavity. The oral surface is covered by stratified squamous epithelium. The epithelium passes down into the crypts in the substance of tonsil. Between the crypts the masses of dense. lymphoid tissue arranged in folds containing the individuals follicles. At intervals, between folds of lymphatic

All these structures contain a matrix of reticular tissue the meshes of which are filled with lymphocytes. In addition to formed lymphatic structures like lymph glands, tonsils, thymus and spleen, there are diffuse lymphatic infiltrations in the body in the mm. Of digestive, respiratory and genital systems and conjunctiva. Tonsils Lymph nodes (Lymph gland) Spleen

Hypophysis cerebri The gross structure of this gland includes two lobes – an anterior and a posterior. Histologically the anterior lobe includes pars distalis or pars anterior and the posterior lobe includes pars nervosa and pars intermedia. Pars tuberalis surrounds the upper part of pars nervosa and is continuous with pars intermedia. Between the pars intermedia and pars anterior there is a cleft.

The adrenal gland is divisible into two distinct different parts – Cortex and medulla that are developmentally and functionally independent. It has a connective tissue capsule containing a few elastic and smooth muscle fibres. From this many delicate trabeculae, enclosing capillaries, penetrate into the cortex and the corticomedullary junction. The framework of cortex consists of

Parathyroid gland are situated very close to or embedded in the thyroid glands. They have connective tissue capsule, but when deeply embedded in the thyroid gland both may have a common capsule. The parenchyma consists of anastomosing cords of cells between which are numerous capillaries. Two types of cells are described. Chief cells: These are polygonal

The Thyroid gland is surrounded by a connective tissue capsule, which gives off septa of varying thickness into the interior. These divide the organ into interconnected lobule consists of vesicles of varying sizes called thyroid follicles. In young animals they are smaller than in adult. Between follicles there is fine connective tissue fibres, which contain many

Endocrine system are organs of internal secretion. They are rich in blood vessels. They have no excretory ducts. and they secrete specific substances called hormones. Thyroid gland Parathyroid gland Adrenal or suprarenal gland Pituitary gland or Hypophysis cerebri