Female Reproductive Microanatomy Summary PDF

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Female Reproductive Microanatomy SummaryFemale Reproductive System includes the Female Genital Tract and the breast (mammary glands)Ovary Functions  Has both exocrine and endocrine functions 1. Production of oocytes and formation of mature ova (exocrine) 2. Production and secretion of 4 hormones (e...

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1 Female Reproductive Microanatomy Summary Female Reproductive System includes the Female Genital Tract and the breast (mammary glands) Ovary Functions  Has both exocrine and endocrine functions 1. Production of oocytes and formation of mature ova (exocrine) 2. Production and secretion of 4 hormones (endocrine) o estrogen o Progesterone o Androgen o Relaxin Ovary Histology  Primary female reproductive organs are ovaries while accessory are the ducts like uterine tubes, uterus, and vagina  The ovaries on the outer side are surrounded by a layer of epithelial cells called the germinal epithelium.  Fibrous connective tissue forms a thin capsule, the tunica albuginea, immediately beneath the epithelium.  The ovary is divided into an outer cortex and an inner medulla. The cortex consists of a very cellular connective tissue stroma in which the ovarian follicles are embedded. The medulla is composed of loose connective tissue, which contains blood vessels and nerves.  Embedded in their cortex are ovarian follicles in various stages of development.  The remains of ruptured follicle after ovulation is called corpus luteum Germinal epithelium of simple cuboidal cells lining the ovary

Three parts of ovary (cortex, medulla, hilum)

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C Histological parts of ovary: Histologically ovaries consists of 3parts 1. Cortex 2. Medulla 3. Hilum – passageway for the lymphatic’s, blood vessels and nerves Cortex or outer portion: 1. germinal epithelium 2. tunica albicans 3. Stroma 4. Follicles at various stages – - primary or primordial follicle, - growing follicle, - mature graafian follicle 5. Corpus luteum 6. Interstitial cells Medulla or inner portion: 1. Loose connective tissue 2. Elastic tissue 3. Smooth muscle fibres 4. Blood vessels, lymphatics and nerve fibres

2 Ovarian Follicles Ovarian follicles consist of one oocyte and surrounding follicular cells. Follicular development can be divided into 4 stages 1. Primordial follicle: (resting condition) single layer of thin simple squamous appearing follicular cells around the oocyt 2. Primary follicle: (activated by FSH) one or more layers of cuboidal,(now called granulosa) cell 3. Secondary follicle: larger (with more ganulosa cells) and with surrounding stromal tissue organized into internal and external thecal layer 4.  Corpus luteum - Following ovulation (under the influence of luteinizing hormone - LH), the ruptured follicle (without the oocyte) reorganizes into a specialized endocrine structure.  After the first trimester of pregnancy, or if pregnancy does not occur, the corpus luteum degenerates into a fibrous tissue scar – corpus albicans

Fallopian Tube (oviduct) The oviduct functions as a conduit for the oocyte, from the ovaries to the uterus. Histologically, the oviduct consists of a mucosa, muscularis and serosa  Mucosa - simple columnar ciliated and secretory epithelium resting on a lamina propria. The number of ciliated cells and secretory cells varies along the oviduct. Secretory activity varies during the menstrual cycle, and resting secretory cells are also referred to as peg-cells. Some of the secreted substances are thought to nourish the oocyte and the very early embryo.  Muscularis Mucosa - consists of an inner circular muscle layer and an outer longitudinal layer. An inner longitudinal layer is present in the isthmus and the intramural part of the oviduct.  Serosa – loose layer of connective tissue

Fallopian tube

The fallopian tube is divided into four parts: 1. The Infundibulum is the funnel-shaped (up to 10 mm in diameter) end of the oviduct. Finger-like extensions of its margins, the fimbriae, are closely applied to the ovary. Ciliated cells are frequent. Their cilia beat in the direction of 2. the ampulla of the oviduct. Mucosal folds, or plicae, and secondary folds which arise from the plicae divide the lumen of the ampulla into a very complex shape. Fertilization usually takes place in the ampulla.

3 3. The isthmus is the narrowest portion (2-3 mm in diameter) of the parts of the oviduct located in the peritoneal cavity. Mucosal folds are less complex and the muscularis is thick. An inner, longitudinal layer of muscle is present in the isthmus and the 4. last, intramural part of the oviduct, which penetrates the wall of the uterus. Ampulla

isthmus Intermural segment

Infundibulum

Uterus Anatomy  Fundus, body, isthmus, and cervix (opens into vagina)  Normal position is anteflexion – anterior and superior over bladder  Ligaments maintain position – broad, uterosacral, cardinal and round Histology – 3 layers 1. Perimetrium – outer layer  Part of visceral peritoneum 2. Myometrium  3 layers of smooth muscle  Contractions in response to oxytocin from posterior pituitary 3. Endometrium – inner layer  Highly vascularized  Stratum functionalis –lines cavity, sloughs off during menstruation  Stratum basalis – permanent, gives rise to new stratum functionalis after each menstruation  The endometrium consists of a simple columnar epithelium (ciliated cells and secretory cells) and an underlying thick connective tissue stroma. The mucosa is invaginated to form many simple tubular uterine glands. The glands extend through the entire thickness of the stroma. The stromal cells of the endometrium are embedded in a network of reticular fibers. 

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Blood supply  Uterine arteries, arcuate arteries, radial arteries  Just before branches enter endometrium divide into  Straight arterioles supplying stratum basilis  Spiral arteries supplying stratum functionalis change markedly during menstrual cycle Cervical mucus - produced by secretory cells of cervix mucosa  Water, glycoproteins, lipids, enzymes, and inorganic salts  More hospitable to sperm near ovulation – thinner, more alkaline  Supplements energy needs of sperm, protect sperm from phagocytes

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Vagina The vagina is a fibromuscular tube with a wall consisting of three layers: the mucosa, muscularis and adventitia. 

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Mucosa: The stratified squamous epithelium rests on a very cellular lamina propria (many leukocytes). Towards the muscularis some vascular cavernous spaces may be seen (typical erectile tissue). Muscularis: Inner circular and outer longitudinal layers of smooth muscle are present. Adventitia: The part of the adventitia bordering the muscularis is fairly dense and contains many elastic fibers. Loose connective tissue with a prominent venous plexus forms the outer part of the adventitia. Anchors vagina to adjacent organs.

Female Accessory Reproductive Glands – Mammary Glands 

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The mammary glands are modified glands of the skin. They are compound branched alveolar glands, which consist of 15-25 lobes separated by dense interlobar connective tissue and fat. Each lobe contains an individual gland. The excretory duct of each lobe, also called lactiferous duct, has its own opening on the nipple. The lactiferous duct has a two layered epithelium - basal cells are cuboidal whereas the superficial cells are columnar. Beneath the nipple, the dilated lactiferous duct forms a lactiferous

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sinus, which functions as a reservoir for the milk. Branches of the lactiferous duct are lined with a simple cuboidal epithelium. The secretory units are alveoli, which are lined by a cuboidal or columnar epithelium. The above description corresponds basically to the appearance of the resting mammary gland. Pregnancy induces a considerable growth of the epithelial parenchyma leading to the formation of new terminal branches of ducts and of alveoli in the first half of pregnancy. Growth is initiated by the elevated levels of oestrogen and progesterone produced in the ovaries and placenta. Concurrently, a reduction in the amount of intra- and interlobular connective tissue takes place. The continued growth of the mammary glands during the second half of pregnancy is due to increases in the height of epithelial cells and an expansion of the lumen of the alveoli....