Embryology Slydes Flashcards
Testis He,Azan
The testis is surrounded by a thick capsule of collagenous connective tissue - tunica albuginea. The tinica albuginea is thickened on the posterior surface of the testis to form the mediastinum testis, from which fibrous septa penetrate the gland, dividing it into pyramidal compartments - testicular lobules.
They have a well defined basal lamina, and a complex germinal, or seminiferous epithelium. The epithelium consists of 2 types of cells: sertoli, or supporting cells, and cells that constitute the spermatogenic lineage.
The spaces between the seminiferous tubules in the testis are filled with connective tissue and interstitial, or leydig cells. These cells produce the male hormone testosterone, which is responsible for the development of the secondary male sex characteristics.
The spermatozoa are covered, when outside of the testis, by a system of tubules:
- tubuli recti - cuboidal epithelium
- ductuli efferentes - nonciliated cuboidal cells, alternating with ciliated columnar cells.
- ductus epididymus - pseudostratified columnar epithelium, composed of rounded basal cells and columnar cells with sterocilia.
IN AZAN STAINED SLIDES, THE TUNICA ALBUGINEA AND THE ACROSOMAL CAP ARE CLEARLY SEEN AT THE TOP OF THE SPERMATOZOON HEAD.
Ovarium He,Azan
The ovary is covered by a cuboidal epithelium - germinal epithelium. Under the epithelium, the stroma forms the tunica albuginea, a poorly delineated layer of dense connective tissue.
The ovary consists of the medullar and the cortical region.
Ovarian follicles are embedded in the stroma of the cortex. A follicle consists of an oocyte surrounded by one or more layers of follicular cells, the granulosa cells. There are several stages of follicular development - primordial, growing and mature follicles. The granulosa cells and the stromal cells of the theca interna secrete a hormone called estrogen.
After ovulation, the granulosa cells and those of the theca interna form a temporary endocrine gland called the corpus luteum, which is localized in the cortical region of the ovary - secretes progesterone.
IN AZAN STAINING THE CONNECTIVE TISSUE STRUCTURES ARE WELL DISTINGUISHED IN BLUE.
Uterus HE
Early proliferative phase - the endometrium or uterine mocusa, consists of an epithelial lining and an endometrial stroma. The epithelial lining is a simple columnar epithelium from which uterine glands extend through the entire thickness of the mucosa.
These are simple tubules that may branch toward their basal ends.
Secretory phase - the endometrium is thick and the glands are markedly coiled and lie within a stroma that appears pale because of the presence of edema fluid with in it.
