endocrine system ductless glands ppt .pptx

endocrine system

1. Endocrine system The endocrine system is a series of ductless glands that secrete messenger molecules called hormones into the circulation.

2. Ductless glands Pituitary Thyroid Parathyroid Thymus S uprarenal pancreas Ovary Tests Others (tissues, cells)

3. Pituitary gland Pacemaker gland of endocrine system definition lies in hypophyseal fossa below the diaphragm sellae . Site avoid shaped Shape 12*8 mm Dimensions: 0.5 g weight It divides into two lobes structure pars distalis . pars intermedia , pars tuberalis , Anterior lobe pars nervosa, infundibular . posteriorlobe sup & inf hypophyseal aa from ICA on each side Arteria supply into surrounded dura venous sinuses cavernous & intercavernous . Venous drainage

4. Pineal gland Part of diencephalon, have endocrine activity definition a short stalk on the roof of the diencephalon. Site conical shape Shape weight; 0.2 gm & long 8 mm & wide 9 mm Dimensions: 0.5 g weight

5. Thyroid gland Secret thyroxine and calcitonin , the largest endocrine gland. definition it lies on the front & sides of the lower part of the neck. site butter fly shaped shape 25 g weight Each lobe 5 cm long, 3 cm width & 2 cm thick Isthmus 1.25 cm height & width dimensions Brownish - red color It consist of two lat lobes & connecting by median narrow part called is isthmus. External structure it composed of hollow, spherical follicles Lying within the follicular epithelium are parafollicular (C)cells Internal structure Superior & inferior thyroid arteries corresponding by veins Blood supply Autonomic sympathetic & parasympathetic Nerve supply

6. parathyroid glands The small, yellow-brown structure Site; lie on the posterior surface of the thyroid gland , The parathyroid cells produce a small protein hormone called parathyroid hormone

7. thymus primary immune organ, act as endocrine & exocrine organ produce thymopoietin & thymosin definition It lies in the superior thorax and inferior neck, just posterior to the sternum. site long 4-6 cm , wide 2.5- 5 cm, thickening 1cm dimensions it consist of two lobes each lobe divides into lobules each which,has inner part (medulla) & outer part (cortex) structure Branches from internal thoracic a Blood supply Autonomic sympathetic & parasympathetic Nerve supply

8. left right definition crescent pyramidal Shape Yellowish color perched on the superior surface of the kidneys left suptarenal gland reach to hilum of kidney . site long 5 cm & wide 3 cm & 1 cm thick & 7-10 g dimensions & weight each gland consist of medulla & cortex structure Directed downloads Directed upwards hilum superior middle and inferior suprarenal arteries. Blood supply left suprarenal vein drain to left renal vein right suprarenal vein drain to IVC Venous drainage Preganglionic sympathetic fibers ending on its chromaffin cells which are homologous with postganglionic sympathetic neurons Nerve supply Suprarenal gland

9. GIT organ act as endocrine & exocrine gland Definition: Shape & color Length – 18 cm & 60 gm. Dimensions & weight lies transversely across posterior abdominal wall extend from concavity of duodenum to hilum of spleen, at the level of 1,2 lumbar vertebrae. Occupied lower part of epigastric & left hypochondrial regions, Site head, uncinate process, neck, body, tail, pancreatic duct ( ampulla of vater , Oddi duct, islets of langerhans structure pancreaticoduodenal arteries Blood supply Parallel to arteries end to portal vein Venous drainage Autonomic sympathetic & parasympathetic fibers Nerve supply

10. testis primary reproductive organ, act as exocrine and endocrine gland (produce testosterone ) definition each testis located in the scrotal sac suspend by spermatic cord site Oval shape length 4 cm, width 2,5 cm, thickening 2 cm dimensions Two poles upper and lower Two borders anterior & posterior Two surfaces medial & lateral structure Testicular Blood supply Autonomic sympathetic & parasympathetic fibers Nerve supply

11. primary reproductive organ, produce Estrogens & progesterone Definition: almond shape Shape: 3,2,1 cm Dimensions: Lies on side of wall of lesser pelvis in a depression called ovarian fossa which has following boundaries: Site Infront&above external iliac a & Behind ureter, internal iliac a It’s has: 2 end, 2 surfaces, 2 borders External structure Internal structure The ovary is surrounded by; a fibrous capsule called the tunica al buginea . capsule outer part houses the developing gametes( oocytes ) cortex a loose connective tissue containing the largest blood vessels, nerves, and lymphatic vessels of the ovary medulla a horizontal slit in the anterior ovarian surface where the vessels and nerve enter to ovary. hilum

12. OTHER ENDOCRINE STRUCTURES The heart. The gastrointestinal tract The placenta The kidneys. The skin