Functional Histology of Reproduction

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What are the effects of castration on the male genital system if performed (i) before puberty (ii) in the adult?

(i) Failure to develop secondary sex characteristics (eg beard, pubic hair, low voice, etc); failure to develop accessory glands. (ii) Atrophy of accessory glands.

Which hormones secreted by the pituitary influence (i) interstitial cells; (ii) the process of spermatogenesis?

(i) LH stimulates interstitial cells to produce testosterone. (ii) FSH controls secretion of androgen binding protein by Sertoli cells, allowing concentration of testosterone within the seminiferous tubules and sperm maturation.

Seminal vesicles Ai

Circular muscle layers Fibrous connective tissue with blood vessels and nerve bundles

Human prostate A- normal glands

Highly vascularised fibromuscular connective tissue separates the glandular elements It can be difficult to differentiate the smooth muscle cells from the fibrous connective tissue

Human uterus, menstrual Ai: stratum compactum

1. Blood vessel 2. Lymphocyte (nucleated cell in a blood vessel) 3. Lumen of the uterine glands 4. 5. Lumen of the uterus

Human uterus, promenstrual, TS: very low power, H&E

Approximately 6th day of menstrual cycle, early proliferative phase The structure of wall of uterus is layered: A. Endometrium (E, mucosa) Composed of three strata: Stratum compactum (SC) the only layer which gets built up in the first part of the menstrual cycle and is discarded at the end of the cycle. Stratum spongiosum (SS) Stratum basalis (SB), containing huge blood vessels B. Myometrium (M, thick muscle) The myometrium contains densely interlaced bundles of smooth muscle, numerous large blood vessels in region adjoining serosa. C. Peritoneum (P, serosa)

What changes would you expect after menopause?

Atrophy, no oocytes, absence of follicles, numerous corpora albicantia, scarred and pitted surface, growth of fibrous tissue, etc

Epididymis

Ductus epididymis: TS through head of anatomical epididymis: Rete testis and efferent ducts Proximal end, not much smooth muscle. Connective tissue running between the coils It is sufficient to be aware of their general structure The tubules sectioned here are ductus epididymis (tubules with regular epithelium and prominent microvilli); tubules with irregular epithelium are efferent ducts At the edge is a portion of the thick testicular capsule, the tunica albuginea. Note the regular tall columnar epithelium with apical microvilli; tubules surrounded by circular/spiral smooth muscle fibres merging into the connective tissue stroma Characteristically the ductus epididymis contains sperm within the lumen

Human testis, adult: high power, iron haematoxylin and eosin

During spermiogenesis the cytoplasm of the spermatid is reduced and phagocytosed by the Sertoli cells as the nucleus condenses and the acrosome forms Synchronous development is enabled by hundreds of spermatids being connected to one another by very fine cytoplasmic processes that persist as the spermatozoa form and which break only when the spermatozoa are released into the lumen A- germinal epithelium containing the Sertoli cells, primary spermatocytes, spermatogonia

Uterus during menstruation

Endometrium and portion of myometrium, during menstruation (2nd day) Note the "weeping" of glandular and stromal debris, mixed with blood, into the uterine lumen

What are the principal histological components of the mammary gland and what changes occur in each of these during pregnancy?

Epithelia - ducts Connective tissue - intra-, interlobular, interlobar; plus BV, nerves and lymphatics, fat Epithelium - proliferation of ducts; secretory units formed; secretory alveoli Connective tissue - progressive reduction in amount; blood vessels increase in number

Human prostate Bbi

Ganglion in the connective tissue 1. Nucleus of a fibroblast in a connective tissue sheath 2. Nucleus of a Schwann cell 3. Myelinated cell? 4. Capillary 5. Nucleolus of a neurone in the ganglion 6. 7. Cytoplasm of a neurone 8. Nucleus of a satellite cell 9. Capillary 10. Something in the nerve bundle

Epididymis A

Here a few tubules are cut in true cross section. Note regularity of the columnar epithelium apical specialisation of epithelial cells with microvilli. 2. How many types of cell are present in the epithelium? Note also the smooth muscle of the tubule and the surrounding connective tissue containing fibroblasts, collagen fibres and small blood vessels. As you get closer to the vas deferens, the amount of smooth muscle increases to 3 layers. Nuclei of spermatozoa in the lumen.

Oviduct

Human fallopian tube (ampulla): very low power, haematoxylin and OG erythrosin The main features are obvious at this low power of magnification: extensively folded mucosa smooth muscle layer numerous blood vessels in adventitia

Human mammary gland Ai

In resting mammary glands the secretory alveoli are virtually absent, but the system of ducts is present The intralobular duct epithelium is usually a single layer of cuboidal cells with basal nuclei The ducts are surrounded by myoepithelial cells (M) which are only lightly stained (and which make the outside of the ducts look fuzzy) Note the abundant capillaries (Cap) in the intralobular connective tissue

Human testis, adult: medium power, iron haematoxylin and eosin

Interstitial cells, or Leydig cells (IC), are endocrine cells that are found dispersed in the loose connective tissue between seminiferous tubules, in irregular clumps of variable size These cells secrete testosterone and are typically endocrine in appearance, with large cytoplasm, round pale nucleus and prominent nucleolus Largely under the influence of luteinising hormone secreted from the pituitary gland. In males, luteinising hormone may be called interstitial cell stimulating hormone, although this practice is deprecated

Breast - pregnancy

Intralobular connective tissue lighter, giving room for growth of the glands In pregnant breast, there are now clearly defined lobules consisting of a mixture of massed ducts with variable numbers of secretory alveoli, the proportion depending on how far pregnancy had advanced Note that the changes are patchy, some lobules showing many dilated irregular-shaped secretory units while others consist solely of ducts The eosinophilic secretion in the ducts is colostrum How have the amounts of intralobular and interlobular connective tissue changed, compared to resting breast? Much less intralobular tissue as the glands have proliferated. In the human, milk production begins 2-3 days after giving birth at which time the secretory units (and thus the lobules) distend further, reducing the connective tissue component to a minimum.

Lactating mammary gland (feline): very low power, H and OG erythrosin

Lactating breast The lobules are a densely packed mass of dilated, irregular, thin-walled secretory units (alveoli) there is no distinction between secretory alveoli and intralobular ducts The lobules are poorly demarcated from one another by thin strands of collagenous connective tissue (the interlobular septa) intralobular connective tissue cannot be seen The secretory units and interlobular ducts contain the secreted milk, seen as an eosinophilic protein coagulum with a foamy vacuolated appearance where the fat droplets have been dissolved out during preparation Note the characteristic tendency for the fatty component of the secretion to separate out and polarise within the alveoli

Ovary Ap

Low / medium power views of the ovarian cortex, containing primordial and primary follicles, a small secondary follicle, and several large secondary (antral) follicles (in which the oocyte is not visible). The points of interest here are: Box A - epithelium, primordial and primary follicles Box B - primary follicles Box C - secondary (antral) follicles

What changes occur at or after ovulation?

Rupture of a single follicle and transport of oocyte to oviduct Transformation of ruptured follicle to corpus luteum ​Degeneration of other maturing follicles (atresic follicles) ​If fertilisation of ovum occurs corpus luteum enlarges and is maintained until third month of pregnancy, otherwise degenerates forming a corpus albicans

Human uterus, promenstrual B: stratum compactum

surface epithelium (E) is only patchily preserved uterine glands (UG) - simple tubular, lined with cuboidal epithelium. Secrete glycogen for nutrition of the blastocyst. endometrial stroma (densely cellular connective tissue with numerous blood vessels) beneath surface epithelium The stratum spongiosum above has fibromuscular tissue.

How would the ovary of a prepubertal female differ histologically from that of a young adult female?

​ Primordial follicles and small antral follicles would be present; no maturing follicles, Graafian follicles present, no corpora lutea or corpora albicantia

What hormones are secreted by the ovary and which structures produce them?

​Oestrogens, progesterone, inhibin (actually a growth factor of the TGFß family) ​Oestrogens are produced by the maturing ovarian follicles and corpus luteum; progesterone by the corpus luteum

Spermatozoa

• Acrosomal cap - vesicle containing cocktail of enzymes (esp. hyaluronidase) to break up cells surrounding ovum and dissolve zona pellucida for fertilisation • Nucleus - containing half complement (haploid number) of chromosomes • Neck - contains residual cytoplasm • Middle piece - first part of flagellum (tail) containing usual "9 + 2" arrangement of microtubules seen in cilia (axoneme) + 9 longitudinal coarse fibres + close-packed mitochondria • Principal piece - remainder of tail containing "9 + 2" microtubules + coarse fibres, tapering to end piece

PENIS

• Contains 3 cylinders of erectile tissue - two dorsal (corpora cavernosa) and one ventral (corpus spongiosum). Erectile tissue contains large, irregular vascular channels, lined by endothelium; surrounded by fibrous tissue with some smooth muscle bundles • Sympathetic nervous stimulation causes partial closure of normal a-v shunt and diversion of blood from helicene arteries into cavernous spaces; outflow of blood is restricted because thin-walled veins are compressed • Corpus spongiosum becomes somewhat less turgid, allowing urethra to remain sufficiently open for passage of semen during ejaculation

EPIDIDYMIS & VAS DEFERENS

• Epididymis is a very long, convoluted duct leading from testes to vas deferens. Site of storage / maturation of spermatozoa (motility develops here). Smooth muscle at distal end has sympathetic innervation and contracts during ejaculation • Vas (ductus) deferens is a thick walled smooth muscular tube that transports spermatozoa to urethra; sympathetic innervation; intense contractions during ejaculation

TESTES

• Fibrous capsule - tunica albuginea - gives rise to fibrous septae that separate testes into 200+ lobules. • Seminiferous tubules - tightly packed into lobules of testes. Tubules lined by multilayer germinal epithelium. Each tubule 0.1-0.2 mm diameter; up to 100 cm long. spermatogenesis (formation of spermatids) + spermiogenesis (maturation to spermatozoa) occurs in co- ordinated waves along each tubule. Sertoli cells rest on basement membrane of tubules and support development of spermatic cells via complex cytoplasmic processes. • Interstitial (Leydig) cells - found in spaces between tubules close to capillaries - secrete androgens (mainly testosterone) in response to luteinising hormone from pituitary. Local concentrations of androgens therefore very high in testes.

SEMINAL VESICLES

• Glands formed by long (~15 cm), convoluted tubular outgrowths from ductus deferens • Responsible for 50% of volume of seminal fluid - thick yellowish-white secretion containing fructose, proteins, amino acids, prostaglandins, citric and ascorbic acids • Thick smooth muscle wall contracts in synchrony with other parts of the genital tract to expel glandular contents during ejaculation (sympathetic innervation)

PROSTATE GLAND

• Large gland surrounding bladder neck + first part of urethra • Glandular epithelium is irregular pseudostratified / columnar • Glandular units produce thin milky fluid that make up 50% of seminal fluid volume. Enzymes in prostatic fluid (esp. fibrinolysin) liquefy coagulated semen some time after ejaculation • Glandular units surrounded by supporting tissue which is a mixture of smooth muscle + fibrous tissue. Contracts in synchrony with other parts of the genital tract to expel glandular contents during ejaculation (sympathetic innervation) • Increases in size (hypertrophy) with age due to androgen stimulation. Growth of innermost part may constrict urethra, reducing urinary outflow. Hypertophy of outermost part may lead to malignant transformation - prostate carcinoma is most common male malignancy (~10% of men affected) • "Prostatic concretions" - calcified lumps - common in lumen of glands, esp. in older men

Female reproductive system - components

• Ovaries (2) - produce oocytes (female gametes) and female sex hormones (oestrogens, progestogens) • Uterinetubes(oviducts,Fallopiantubes)(2) - conduct ova towards uterus; fertilisation occurs along tube • Uterus - where embryo implants and grows; cervix • Vagina - site of introduction of spermatozoa; birth canal • Breasts - produce of colostrum & milk - nutrition of newborn

Breast

• Production of colostrum & milk - nutrition of newborn • Epithelia - ducts & glands • Connective tissue - intra-, interlobular + BVs, nerves and lymphatics, fat

Spermatogenesis

• Spermatogonia - germ cells (present in small numbers before puberty) - multiply by mitosis to give continuous supply of cells for meiosis... type A spermatogonia undergo asymmetric division (mitosis) → more type A cells + type B spermatogonia → 1o spermatocytes • Primary spermatocytes - undergo 1st meiotic division (takes ~3 wks), producing.... • Secondary spermatocytes - daughter cells of 1st meiotic division - (hard to see) rapidly undergo 2nd meiotic division to produce.... • Spermatids - undergo ~7 wk maturation process (spermiogenesis) to produce.... • Spermatozoa - final stages of maturation take place in epididymis

Uterus

• Where embryo implants and grows - simple and secretory columnar epithelium with uterine glands; cervix • Cyclical monthly changes • Proliferation - endometrium doubles in thickness; simple tubular glands form • Secretion - begins with ovulation - glycogen main nutritive product endometrium reaches maximum thickness; highly vascular • Degeneration (menstruation) - in absence of implantation of fertilised ovum

Ovaries

• produce ova (female gametes) by the process of oogenesis • produce female sex hormones - oestrogens (via action of aromatase in granulosa cells on androgen precursors produced by thecal cells) - inhibin (inhibits FSH; granulosa cells) - progestogens (corpus luteum)

Male reproductive system

Production, nourishment and short-term storage of spermatozoa • Introduction of fluid containing spermatozoa into female genital system • Synthesis of male sex hormones (androgens) • Testes (2) - produce spermatozoa (male gametes) and male sex hormones (androgens) • Ducts - efferent ducts (2) → epididymis (2) → ductus (vas) deferens (2) → ejaculatory ducts (2) → urethra → .... • Glands - seminal vesicles (2) + prostate (1) + bulbourethral glands of Cowper (2) • Penis

Lactating Mammary gland i

What are: 1. Septa 2. Secretory unit (sometimes referred to as alveolar) 3. Lumen of a duct

Lactating mammary gland iA

What are: 1. Lipid material creamy component of the milk, split from the aqueous component 2. Blood vessel

Lactating mammary gland iC: duct

What are: 1. Surrounding septa- collagenous connective tissue 2. Duct

What tissues form the erectile tissue of the penis? Which nerves innervate it?

"Spongework" consisting of a network of endothelial lined vascular sinuses (irregular blood channels) surrounded by connective tissue and strands of smooth muscle. Sensory and autonomic innervation.

recognise a section through the ovary (cat)

(Cats have several Graafian follicles that rupture) Very low power view of longitudinal section of mature ovary (cat); non-pregnant (toluidine blue stain?). The human ovary is considerably larger, measuring about 1 x 2 x 3 cm. At low magnification, many follicles can be seen at various stages of development. The 'services' for the ovary are carried in through the hilum to the broad ligament which is not shown in this image. Large numbers of primordial (arrested at the first meiosis division) and primary follicles are located in the cortex, close to the outer epithelium. At least 30 secondary follicles at various stages of development are visible, some of which include the oocyte in the plane of section; the largest, most mature follicles lie near the surface of the ovary as they approach ovulation. There are no corpora albicantes in this ovary (although there are a few atretic follicles): this finding, plus the numerous cortical oocytes gives an indication of the age of the animal. What would you suggest?

Name the four main components of the male reproductive system and their functions. Name the epithelium lining each.

(a) Testes - gonads: produce sperm; testosterone; two testes containing numerous highly coiled seminiferous tubules lined with stratified germinal epithelium. (b) Genital tract: modification of testicular secretions; storage; expulsion. Ducts connecting testes to urethra; for each testis - efferent ducts, the ductus epidydimis, and the ductus (vas) deferens; function - modification, collection, storage and conduction of spermatozoa; pseudostratified columnar epithelium with long microvilli (stereocilia). (c) Accessory (exocrine glands) glands: fluid components of semen; paired seminal vesicles and a single prostate gland; function - secretion of nutritive seminal fluid; simple columnar/cuboidal secretory epithelium (or pseudostratified) in seminal vesicles and prostate; also, bulbo-urethral glands - mucous secretion, lubrication. (d) Penis: ejaculation of semen into female genital tract; pseudostratified columnar epithelium.

Uterine tubes

(oviducts, Fallopian tubes) - conduct ova towards uterus, fertilisation occurs along tube simple cuboidal / columnar epithelium of ciliated cells and secretory cells

Oviduct iB: adventitia

What is the orientation of the smooth muscle in the muscularis propria? Both longitudinal and circular What can you say about the innervation of the fallopian tube? Subject to sympathetic Innervation, small nerve bundles are seen.

Human vaginal cervix B

What type of epithelium is present at the edge on the right? Squamous epithelium What apical specialisation does it have? What is present immediately beneath this epithelium (beneath its basal lamina)? What feature is evident in this region? What are the labelled items: 1. 2. 3. Lumen of the cervical canal 4. Lumen of cervical mucous glands 5. Capillary 6. Capillary

Ovary Ci

What type of follicle is this? Secondary follicle, antral follicle What are the labelled items: 1. Antrum 2. Zona granulosa 3. Theca interna 4. Theca externa 5. Oocyte 6. Zona pellucida 7. Corona radiate 8. Capillary 9. Ovarian stroma What is the status of the oocyte?

Human testis, adult: high power, iron haematoxylin and eosin

1. Nucleus of smooth muscle in the musculofibrous capsule 2. Cytoplasm of musculofibrous capsule cells 4. Type B spermatogonia 4. Collagen or reticular fibres in ECM 5. Spermatid 6. Sertoli cell 7. Spermatozoa 8. Primary spermatocyte 9. Type A spermatogonia 10. Leydig cells

Seminal vesicles Aii

1. Smooth muscle wall of an artery or arteriolar 2. Smooth muscle 3. Arteriole? 4. Nucleus of a Schwann cell from a nerve bundle 5. Capillary 6. Lymphocyte (uncleared blood cell) 7. Nucleus of an endothelial cell

Human vaginal cervix A

1. Stratified squamous epithelium continuous with the vagina 2. Simply columnar epithelium 3. Epithelium of a cervical mucous gland (behind the stratified squamous epithelium) 4. Endothelial cells of an arteriole

Human vaginal cervix D

What types of epithelium are: 1. 2. 3. 4.

Human vaginal cervix Di

What unfortunate event often happens at A? Why? What are the labelled items: 1. 2. 3. 4. 5. 6.

Human vaginal cervix Ai

A- transition between stratified squamous and simple columnar epithelium 1. Cervical stroma 2. Vein 3. Squames of the stratified squamous epithelium 4. Simple columnar epithelium 5. Lymphatic 6. basal cells Possibly inappropriate crosstalk between the two types of epithelium as their growth is regulated by different factors can cause the stratified squamous epithelium to undergo neoplasia. This occurs in addition to cofactors such as carcinogens and HPV.

Ovary during pregnancy

CA- corpus albicans, lumps of scar tissue that remain after the corpus luteum of menstruation begins to involute and degenerate. Human ovary (pregnant, corpus luteum): very low power, H&E Note the single corpus luteum of pregnancy that occupied about two thirds of the volume of the ovary Secondary follicles (S) are relatively small and collapsed Note the prominent theca of the secondary follicles, a feature of pregnancy The very palely stained blobs are corpora albicantes (CA) Of what is a corpus albicans made? Strands of theca lutein (TL) cells (fairly small cells) may be seen penetrating from the periphery into the main mass of follicular lutein cells (large and vacuolated). Androgens are produced here and are converted in the granulosa cells by aromatase to oestrogen. The granulosa cells also produce progesterone. Underneath are the granulosa lutein cells The central cavity of the corpus luteum (persisting from the ovulated secondary follicle) contains a fuzz of protein precipitate and loose connective tissue, formed by invading thecal connective tissue cells The hilum (H) and broad ligament (L) are present in this image where the major blood vessels come in. Note the large blood vessels: these are branches of the ovarian and uterine arteries (which branch off the aorta) Ovarian stroma is full of small blood vessels, especially capillaries surrounding follicles There will also be veins and lymph vessels here

Cervix & vagina

Cervix - neck of uterus; birth canal - simple epithelium; abrupt transition to stratified squamous epithelium of vagina is frequent site of malignant transformation Vagina - site of introduction of spermatozoa; birth canal - stratified squamous epithelium

Seminal vesicle C

Columnar epithelium Fibromuscular tissue underneath the folds of the epithelium

Ovary ApB

Cortex of the ovary The largest follicle in this image is a primary follicle Primordial follicles on the outside, surrounded by flattened cells The primary oocyte (O) has enlarged The granulosa cells have multiplied mitotically and formed a zona granulosa (ZG) The ovarian stromal cells have begun to organise themselves around the follicle, forming the theca folliculi (TF) The space between the oocyte and the zona granulosa in this image is an artefact

Which cells of the testis are especially sensitive to X-rays and anti-mitotic drugs?

Dividing cells of the germinal epithelium high dosages would cause atrophy of germinal cells; Sertoli cell population spared; infertility.

Human mammary gland, resting: very low power, H and OG erythrosin

Milk is a complex secretion containing protein, carbohydrate and a high fat content, all secreted by a single type of gland cell and stored within secretory units (alveoli) during pregnancy and lactation In the reproductive female the histological appearance of the mammary glands is determined by the level of secretory activity The functional states are: Resting - non-secretory Pregnancy - preparation for lactation Lactation - milk secretion Regression - the gradual return to the resting non-secretory state Note the preponderance of connective tissue in the non-secretory gland the epithelial component is almost entirely represented by ducts (the big white shapes) few (if any) secretory units (alveoli) are present The terminal ducts are arranged in clusters separated by dense fibrous connective tissue, a typical lobular pattern Identify: intralobular ducts and connective tissue lighter interlobular ducts and connective tissue darker Note the differences in texture and collagen fibre density between the intralobular and interlobular connective tissue Proceed via the interactive areas Box A - secretory tissue Box B - collecting duct

Human mammary gland, pregnant B

Note that the epithelium of the intralobular ducts has proliferated and many of these ducts now have a two-layered epithelium

Human uterus, promenstrual Bi: stratum compactum

Note the high cellular density of the stroma and the paucity of collagen fibres

Oviduct iA

Note variable appearance, simple or pseudostratified with basal cells, cuboidal or columnar

What histological changes occur in maturing ovarian follicles before ovulation?

Oocyte - increase in size; zona pellucida Follicular epithelium (granulosa), followed by increase in follicular fluid in central cavity ​Development of hormone secreting thecal cells

Ovary ApA

Ovarian epithelium The cortical surface is smooth, covered with a simple cuboidal epithelium (E), often only patchily preserved Beneath the epithelium is a layer of fibrous connective tissue, the tunica albuginea (TA), be careful of the context, the testis also has a tunica albuginea Primordial follicles (PF) consist of primary oocytes (O) surrounded by a single layer of flattened follicular cells (F) Often the oocyte are out of site, such is the case with the primary follicle here In this image there is a single early primary follicle whose follicular cells have multiplied and have become cuboidal granulosa cells (GC)

Human uterus, promenstrual C

Some blood vessels of the enormously vascular region of the uterine wall Recognise arterial and venous vessels The arterial components are the straight arteries, which supply the stratum basalis The withdrawal of progesterone at the end of the menstrual cycle causes these helical arteries to constrict cutting off the blood supply to the stratum compactum to degenerate and be discarded.

Human testis, adult: medium power, iron haematoxylin and eosin

Spermatozoa in seminiferous tubules In this image many tubules are cut obliquely Note how some tubules conatain mature, flagellated spermatozoa while some do not This is because spermatozoa are in different stages of development in different regions of tubules, but are in the same stage of development in any given region.

What are Sertoli cells, where do you find them, and what is their function?

Supportive cells of the germinal epithelium of the seminiferous tubules. Function - support, protect and nourish developing sperm cells; secretion of hormones/growth factors; phagocytosis.

Vas deferens

TS through spermatic cord; adult human, H & E, containing the ductus deferens (vas deferens) This image shows a large quadrant of a transverse section of the vas deferens This muscular tube is surrounded by a sheath of connective tissue The adventitia has large blood vessels and nerves. 3 muscular layers- Inner and outer layer of longitudinal muscle with an intermediate circular layer. The lumen lined by columnar epithelium with room to expand during ejaculation

Human prostate

The Prostate Gland The prostate gland surrounds the urethra between the base of the urinary bladder and the base of the penis This specimen is not normal; there is evidence of previous infection, with epithelial changes in the secretory alveoli and cyst formation. Observe by naked eye the general architecture of the glandular tissue (compound exocrine, alveolar secretory units); cystic areas of glandular tissue can be seen and are patchily distributed Note the relationship of the urethra to the glandular tissue In this region the urethra is called the prostatic urethra and it has a crescentic lumen, its epithelium is transitional (continuous with that of the bladder) and it becomes simple or pseudostratified columnar as it leaves the prostate gland to become the membranous urethra. In the penis the spongy urethra has a simple or pseudostratified columnar epithelium, except at its exit at the end of the penis where it is stratified squamous The prostate gland is encapsulated The capsule contains fibroelastic connective tissue. Connective tissue septa from the capsule divide the gland into poorly defined lobules. The connective tissue also contains irregular bundles of smooth muscle cells (which contract under sympathetic control) The prostatic glands drain into ducts which coalesce and eventually drain into the urethra on each side of the urethral crest. In this image, large prostatic ducts may be seen converging on the urethra

Human prostate B

The capsule (Cap) of the prostate gland is a fairly thick layer of fibroelastic connective tissue with smooth muscle cells (difficult to identify with this stain) In this image, in the surrounding adventitia you should be able to identify these elements: fibrous connective tissue adipocytes blood vessels (arterial and venous) lymphatics nerve bundles a parasympathetic ganglion (terminal ganglion) In older men, the lumen of the glands often become filled with prostatic concretions (Box A)

Human mammary gland A

The difference in density between intralobular and interlobular connective tissue is readily apparent in this image. The intralobular connective tissue is less dense as it gives the glands room to grow during pregnancy. The milk producing glands are not very well developed as they are in the resting state Note the presence of adipocytes. A few blood vessels can be seen as well.

Oviduct iAi

The epithelium is ciliated, but the cilia are not well preserved What are: 1. Columnar epithelium 2. 3. 4. What does the lamina propria contain? Some smooth muscle What types of cell are present in the epithelium? Regular columnar epithelium, some are ciliated, some are not and there are intercalated cells. The cilia will waft the oocyte into the right direction. The non-ciliated cells secrete the fluid in the fallopian tube.

Human mammary gland Bi

The epithelium of the collecting ducts is usually two layers of cuboidal cells Immediately beneath this epithelium the connective tissue is loose and highly vascularised with microvessels The duct contains a secretion which is not milk or colostrum Intralobular and interlobular ducts are affected by ovarian hormones, and as their circulating levels rise during the menstrual cycle the ductal cells are stimulated to secrete slightly and the ducts distend (increasing the firmness of the breast at this time)

How does the testis of a child differ from that of a normal adult?

The epithelium of the seminiferous tubules consists mainly of Sertoli cells and with spermatogonia; the sperm cells develop and differentiate under the influence of testosterone which starts to be secreted at puberty.

Human prostate Ai

The glandular epithelium (E) is pseudostratified cuboidal or columnar, and is highly branched or folded The lamina propria (LP) contains a core of connective tissue and carries the services.

Human prostate Ba

The lamellated object is a corpus amylaceus, and is made out of glycoprotein With age these become calcified to form true prostatic concretions, completely takes up the gland.

Human mammary gland, pregnant i

The large collecting duct contains precipitated colostrum

Oviduct i

The layers are: Adventitia Muscularis propria running in circular and longitudinal directions Mucosa lamina propria epithelium Box A - mucosa Box B - muscularis and adventitia

Ovary A

The left half of this image is ovarian cortex, containing: Primordial follicles (P) Primary follicles (1) Secondary follicles (2) Secondary follicles may be called antral follicles N.B. The definition of primary, secondary and tertiary follicles can be confusing - different texts will tell you different things. For this reason, the terms "pre-antral" and "antral" are preferred, describing follicles without and with an antrum, respectively Graafian follicles are the most mature type of antral follicle and are the follicles that rupture at ovulation In any one cycle, only one antral follicle will become the Graafian follicle Graafian follicles are always towards the cortex and bulge beneath the ovarian epithelium (whose cells flatten) Large antral follicles such as (3) should not be called Graafian follicles unless the oocyte status is known

Ovary C

The left side of this image is ovarian medulla, which is quite vascular The pale pink spots here are corpicus albicans Note also the number of atretic follicles. These are the remains of secondary follicles that have not gone onto ovulation The follicles that began to mature in a menstrual cycle but which did not become the Graafian follicle undergo atresia

Human vaginal cervix D:

What type of epithelium is this? Is it keratinised? The "peg" at the base of this epithelium is a papilla, similar to those found in skin. Papillae can reach deep into the epithelium and contain blood vessels, i.e. capillary loops (Cap), and autonomic and sensory nerve fibres. The nerves are involved in controlling the capillary permeability and are thought to control the transudation that performs the function of lubrication

Human testis- germinal epithelium

The seminiferous epithelium is an example of a germinal epithelium Spermatogonia are found in the basal layers resting on the basement membrane, they divide mitotically to give rise to further stem cells called Type A spermatogonia, and Type B spermatogonia Type A spermatogonia (SA) have large dark nuclei (condensed chromatin) with peripheral nucleoli (if visible) Type B spermatogonia (SB) have large pale nuclei (dispersed chromatin) with central nucleoli. Type B cells enter mitosis and become spermatocytes Primary spermatocytes (S1) are the largest cells here, with distinctive nuclei in which the chromatin is in clumps or threads. They divide in the first meiotic division to yield two daughter cells, secondary spermatocytes. The first meiotic cycle takes about three weeks, but the secondary spermatocytes (rarely observed) rapidly undergo the second meiotic division to produce the gametes, spermatids (ST) Spermatids mature during spermiogenesis and become spermatozoa (SZ), changing their appearance from small round cells to smaller pointed cells Sertoli cells (SC) support the spermatogenic cells They rest on the basement membrane and extend to the lumen, their nuclei are usually oval or triangular, pale with a prominent nucleolus above the basal level. Their cytoplasm surrounds the spermatogenic cells and Sertoli cells make tight junctions with each other, thus providing a cellular barrier between the circulation and the spermatogenic cell, the so-called blood testis barrier The germinal epithelium with is basal lamina sits on a thin layer of fibromuscular connective tissue, with fibromyocytes (myoid cells, myoepithelial cells) dispersed amongst collagen and elastin fibres that they have laid down

What would be the appearance of an undescended abdominal testis in an adult, and why?

The seminiferous tubules will contain Sertoli cells and interstitial cells secreting testosterone will be present; the temperature sensitive germinal cells will however not develop, so no spermatogenesis.

Promenstrual uterus

The stratum functionalis is what is lost during menstruation Th drop in progesterone and oestrogen during menstruation constrics the vessels suppyling the endometrium leading to their degenration

Human uterus, menstrual A: stratum compactum

The surface epithelium is absent; eroded uterine glands and raw endometrial stroma from the ragged exposed surface Glycogen can be seen in the glands which serves as nutrition for the blastocyst (pale orange smudges) This tissue makes up the bulk of the menstrual flow.

Secondary/Graafian follicle

The theca interna cells are the endocrine cells

Epididymis B

The tubules contain agglomerated spermatozoa (is this real or artefactual?) The wall of the tubule consists of: an external adventitia of connective tissue that merges with the connective tissue between the tubules an outer layer of smooth muscle, oriented predominantly circularly or obliquely (spirally) subepithelial connective tissue (a thin layer) an inner lining of simple columnar epithelium Note the presence of blood vessels in the connective tissue between the tubules At the top right there is a small segment of the tunica albuginea. What is its construction?

Seminal vesicles B

The wall of the seminal vesicles consists of (from the outside to the inside) Adventitia Muscularis- inner circular and outer longitudinal layer Submucosa Mucosa What are: A B C D- adventitia with nerve bundle What are the major components of these layers?

Primary/primordial follicles

Thecal cells around the primary follicle ~ 500,000 PF in human ovary at birth - arrested in 1st meiotic division ~ 20 / month begin maturation... only 1 ovulates usually

Human mammary gland B

This collecting duct is embedded in interlobular connective tissue What type of connective tissue is this, and what does it contain?

Seminal vesicles

This image is of a section of a segment of seminal vesicle, showing surrounding connective issue (bottom left), the fibromuscular wall (diagonally) and a part of the lumen (top right, containing precipitated fluid)

Human testis

This image shows seminiferous tubules cut in various planes Each seminiferous tubule is surrounded by a sheath (collagen plus contractile myoepithelial cells) Vascular connective tissue stroma contains clumps of interstitial cells (Leydig cells). Grey-purple cells are the Leydig cells

Cervix

This is a midline section and therefore includes the cervical canal and its opening into the vagina (the external os); only a limited amount of vaginal wall is included (on the right) Follow the continuity of the vaginal cervix with the wall of the vagina, along the stratified squamous epithelium over the vaginal surface of the cervix to its orifice (the external os): at this point, or a short way along the cervical canal, there is an abrupt change to the simple cuboidal/columnar epithelium which lines the rest of the uterine lumen (Box A) Note the branched mucous secretory glands (G) opening into the cervical canal, and the secretions in the cervical canal (a mixture of mucus and shed cells) The stroma of the cervix is made of fibromuscular tissue Proceed via the interactive areas Box A - vagina/cervix junction Box B - wall of cervix Box C - vaginal stroma Box D - vaginal epithelium

Human uterus, promenstrual A: stroma

What are the labelled items: 1. Endothelial cell 2. Nucleus of muscle cell 3. Nucleus of fibroblast 4. Fibromuscular cells of the stroma 5. 6. Smooth muscle wall of blood vessels 7. Fibrous connective tissue which the blood vessels run in 8. Capillary Note the difference between the connective tissue around the two blood vessels and the uterine stroma These are probably spiral arteries, which, like the straight arteries, are derived from the uterine artery. They supply the endometrium with a rich vascular plexus that degenerates, and bleeds, during menstruation

Lactating mammary gland iB

What are: 1. 2. 3. 4. 5. 6.

Ovary ApC

This is a young-ish antral (secondary) follicle The main difference between a primary follicle and a secondary follicle is the development of the antrum (A), which is filled with follicular fluid, due to proliferation of the granulosa cells The granulosa cells become endocrine at this stage, secreting follicle stimulating hormone (FSH) and converting androstendione (secreted by thecal cells) into oestrogen Note that the pituitary gland secretes far more FSH than the granulosa cells, whose output is very low At ovulation the granulosa cells secrete inhibin F which inhibits pituitary FSH production The primary oocyte has reached its maximum size The zona pellucida (ZP), which is present in late primary follicles, is well developed, surrounding the oocyte and separating it from the granulosa cells The theca folliculi differentiates into the theca interna (TI) and the less distinct theca externa (TE) The cells of the theca interna tend to round up and form a layer a few cells thick. These are endocrine cells, they secrete oestrogen and progesterone to promote proliferation of the uterine mucosa, preparing it for implantation of a fertilised ovum The cells of the theca externa become flat and fusiform, merging with the stroma

Ovary B

This is an antral follicle at a late stage The antrum has enlarged, surrounded by an even layer of zona granulosa a few cells thick The region where the granulosa cells maintain the attachment of the oocyte is the cumulus oophorus

Human vaginal cervix C: stroma

This is vaginal stroma Type 1 collagen fibrils Blood vessels Fibroblast Nerve bundles What are the two main tissue types present here? What other structures are present?

Name the components of the female genital tract and relate to function. ​What type of epithelium lines each part?

Uterine tubes (oviducts, Fallopian tubes); simple cuboidal/columnar epithelium of ciliated cells and secretory cells; conduct ova towards uterus, fertilisation occurs along tube. Uterus where embryo implants and grows; simple and secretory columnar epithelium with uterine glands; cervix; simple columnar epithelium with mucous secreting glands. Vagina; stratified squamous epithelium

Human uterus, menstrual B: permanent stroma of the endometrium

Vessels under the stratum basalis (straight arteries) are unaffected by menstruation

Human mammary gland, pregnant iA

What are the labelled items 1. 2. 3. 4. 5. 6. 7. 8.


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