Male Reproductive System Flashcards
Seminiferous tubules are enclosed by….., rich in….., their function is……
Myoid cells
rER
Have a role in collagen synthesis & have rhythmic contractions that aid in movement of spermatozoa along length of tubule
Spermatogenic cells are arranged in …..layers, they are……
4-8
Spermatogonia, 1ry spermatocytes, 2ry spermatocytes, spermatids
Mention the result of divison of each of the following:
1. Dark type A spermatogonia
2. Pale type A spermatognoia
3. Type B spermatogonia
- Dark type A & pale type A
- Pale type A & type B
- Primary spermaticytes
Dark type A act as……but pale act as……
Reserve stem cells
Undifferentiated stem cells
Type B spermatogonia divide by……under effect of…..
Mitosis
FSH
The largest spermatogenic cells are……, they are most common in section because…….
1ry spermatocyte
It remains in prophase I of meiosis for about 22 days
Describe genetic composition of:
1. Spermatogonia
2. 1ry spermatocytes
3. 2ry spermatocytes
4. Spermatids
- 46 S-chromosones (2N)
- 46 D-chromosomes (4N)
- 23 D-chromosomes (2N)
- 23 S-chromosomes (1N)
Describe course of the following:
1. 1ry spermatocytes
2. 2ry spermatocytes
3. Spermatids
- Enter S phase of cell cycle where DNA is duplicated & enter first meiotic divisoj to give 2ry spermatocytes
- Enter 2nd meiotic division to give 2 spematids without S phase
- Transforms into spermatzoon by spermiogenesis
Spermatogenesis consists of……&….
Spermatocytogenesis
Spermiogenesis
List stages (general) of spermatocytogensis +brief note
- Proliferation: spermatogonia divide by mitosis
- Growth of daughter type B spermatogonia to give 1ry spermatocytes
- Maturation includes 1st meiotic divison & 2nd meiotic divison
After meiosis, Daughter cells are attached to each other by…….., whose function is…….
Intercellulr bridges
Allows genetic cross talk between haploid cells and synchronous development of each clone from type A spermatogonia
Define & List stages of spermiogenesis
It is transformation of spermatids into spermatozoa without divison
Golgi, cap, acrosomal phases
Mention events that occur in Golgi phase of spermiogenesis
- Golgi complex becomes near the nucleus, small PAS +ve granules appear in golgi complex called proacrosomal granules
- Fuse together & are enclosed with a membrane to form acrosomal vesicle adjacent to nuclear membrane
- At the same time, the 2 centrioles migrate to opposite pole of nucleus, the distal one acts as basal body organizing axoneme of flagellum
Mention events that occur in Cap phase of spermiogenesis
- Acrosomal vesicle spread over ant half of nucleus forming cap
- Nucleus becomes condensed & the nuclear membrane thickens & loses its pores
- Acrosome contains hydrolytics (phosphatase, protease called acrosin) that help penetration of zona radiata & pellucida of 2ry oocyte
Mention events that occur in acrosomal phase of spermiogenesis
- Nucleus forms head of sperm
- Nucleus & acrosome move to ant plasma membrane & the cytoplasm is displaced posteriorly
- Cytoplasmic microtubules become organized into cylindrical sheath, Manchette, where extends from post part of acrosomal cap towards posterior pole of spermatid
- Distal centriole moves to post surface of nucleus & forms flagellum
- In neck region, nine coarse fibers produced from centriole surrounding the microtubules of the axoneme
- Mitochondria are arranged around the proximal part of the flagellum to form the thickened middle piece of the sperm, which stop at annulus
- Plasma membrane moves posteriorly to cover the flagellum
- Movement of the flagellum is due to interaction among microtubules ATP & dynein which is a protein with ATPase activity.
Mention events that occur in maturation phase of spermiogenesis
The excess cytoplasm is shed off as residual bodies which are phagocytosed by Sertoli cells, intercellular bridges are lost, spermatozoa are released into lumen of seminiferous tubules & remain immotile until they leave the epididymis.
Neck of sperm contains……….
Centriole & a connecting piece which forms the 9 coarse fibers that will surround the axoneme
Tail of sperm is composed of……..
Middle piece, principle piece, end piece
Mention components of middle piece
- Axoneme: 2 central singlets, 9 peripheral doublets
- Nine coarse longitudinal fibers that arise from connecting piece of the neck
- Tightly packed elongated mitochondria forming mitochondrial sheath to provide the necessary energy for flagellat motility
- Plasma membrane
Immotile cilia is due to………
Lack of dynein or other proteins required for motility of cilia
Apical cell membrane of Sertoli cells shows……..
Infoldings that contain head of the sperms (LM)
Pockets to embrace the spermatogenic cells (EM)
Describe connections of Sertoli cells & their functiom
- Tight junctions, divide seminiferous tubule into basal (spermatogonia) & adluminal (spermatocytes, spermatids, sperms) compartments
- Gap junctions, provide ionic & chemical transport between cells
Sertoli cells have receptors for…..
FSH
How do spermatocytes pass between compartments of seminiferous tubules
Newly formed spermatocytes temporarily disassemble the occluding junctions & move into adluminal compartment while germ cells remian linked by intercellular bridges.
Describe importance of blood testis barrier
- Provide soecial environment for growth & differentiation of spermatogenic cells
- Protection of spermatids & spermatocytes from any harmful substances present in the blood
- Prevent passage of sperm into blood causing autoimmune reaction
- Prevention of passage of antisperm Ig
Describe LM & EM features of interstitial cells of Leydig then mention their function
LM: surround fenestrated b.c., rounded or polygonal cells with acidophilic vacuolated cytoplasm and central rounded vesicular nuclei
EM: have chcts of steroid secreting cells, well-developed sER, prominent golgi, mitochondria with tubular cistae & lipid drplets. They contain crystals in Rienke which are elongated rectangular masses not seen before puberty & inc in number during yrs of sexual maturity.
They secrete testosterone under effect of ICSH, which is responsible for development of 2ry male sex chcts
Tubuli recti are lined by……..in initial segment &…..in main segment
Sertoli cells
Cuboidal epithelium
Rete testis is lined by…….
Cuboidal epithelium
Vasa efferentia are……in number lined by……
10-20
Simple columnar ciliated cells alternating with groups of cuboidal non-cilitaed cells
What is the function of intratesticular genital ducts?
- Cilia beat in direction of epididymis to move immotile sperms
- Non ciliated cells reabsorb some of testicular fluid
- The thin layer of circularly oriented smooth muscle cells aid movement of sperm into duct of epididymis
Describe lining of epididymis
Lined by pseudostratified columnar epithelium consisting of columnar principal cells with chct sterocilia and small round stem cells.
What is the function of epididymis?
- It stores the sperms
- The principle cells reabsorb about 90% of testicular fluid & phagoctose remnants of the rsidual bodies that are produces during spermatogensis
- Its cells secrete specific proteins & glycoproetins necessary for sperm maturation
Describe changes in spermatozoa while passing through epididymis
- Final modifications within acrosome
- Reorganization of the cell membrane surrounding sperm head including addition of cholesterol & other decapacitation factors which block acrosomal reaction until female reproductive tract.
- Development of competence for forward motility
Epithelium of vas deferens is……., while musculosa consists of………
Pseudostratified columnar epithelium with stereocilia
Inner longitudinal, middle circular & outer longitudinal smooth muscle fibers
Ejaculatiry duct is lined by……..
Simple columnar epithelium
List components of spermatic cord
- Vas deferens
- Testicular artery & vein
- Paminiform plexus of veins
- Nerves
- Involuntary striated cremasteric muscle
Epithelium of seminal vesicles is……& musculosa consists of……
Simple columnar cells with patches of pseudostratified columnar cells rich in secretory granules
Formed of inner circular & outerlongitudinal smooth muscle fibers
Prostate gland type is………, its capsule is rich in……
Compound tubulo-alveolar gland
Smooth muscles
Prostate parenchyma consists of…..glands arranged in ….zones which are…….
30-50
3
Central, transitional, peripheral
Describe lining epithelium of glands of prostate
Simple cubical, simple columnar, pseudostratified columnar according to glandular activity
Lumen if prostate glands contains calcified bodies called……
Corpora amylacea
What is PSA?
A protease which helps liquefy coagulated semen for the slow release of sperm after ejaculation.
Malignant prostatic tumors arise from…….
Main acini
Cowper’s glands are…….
Small tubulo-alveolar glands
Bulbo-urethral gland is lined with…………, their small ducts are lined by……., while large ducts are lined by…….
Mucus-secreting simple columnar or cuboidal epithelium
Simple secretory epithelium
Stratified columnar epithelium
Two corpora cavernosa contain……, while corpus spongiosum contains……
Central or deep artery
Penile urethra
Explain: Corpora are formed of erectile tissue
They are formed of venous spaces lined with non fenestrated endothelial cells and separated by trabeculae of collagenous fibers, elastic fibers & smooth muscle fibers
The commonest malignant tumor of testis is……., its types are…….
Seminoma
Classical & spermatocytic
Describe microscopic features of
1. Classical seminoma
2. Spermatocytoc seminoma
- It is made up of masses of large cells with abundant pale or clear cytoplasm and large nuclei separated by thin stroma which is usually iniltrated by lymphocytes and often contain epithelioid granulomas resembling those of sarcoidosis. Lymphocytic infiltrate and the granulomas are favorable prognostic sign
- Neoplastic cells resemble 2ry spermatocytes, it lacks the lymphocytic infiltrate and granulomas, never send metastases & never mixed. Better prognosis & older age.
Describe prognosis of seminoma
- Seminomas are remarably radiosensitive
- About 95% of patients with spread to the para-aortic LNs
- Remains localized for long time & even those with lung mets have good prognosis after radiotherapy.
Describe gross & microscopic features & prognosis of embryonal carcinoma
G: differs from seminoma by being poorly demarcated, showing Hge & Nec
M: it is made up of large pleomorphic malignant cells with an epithelial appearance arranged in glands, irregular papillae & sheets. The stroma does not contain lymphocytes or granuloma
P: more aggressive & lethal than seminoma
Describe microscopic features of Yolk sac
It consists of spaces & papillae lined by flattened to cuboidal malignant epithelial cells containing eosinophilic hyaline globules +ve AFP. Show chct Schiller-Duvall bodies
Choriocarcinoma is made up exclusively of………., responds to……..
Malignant cyto and syncytiotrophoblasts
Chemotherapy
Prognosis of combined germ cell tumors depends on……
The most malignant element present
List tumors which show the following markers:
1. hCG
2. AFP
- Seminoma (10%), choriocarcinoma (100%), mixed (90%)
- Yolk sac (90%), mixed (90%)
Sertoli cell tumors produce……while Leydig cells produce……
Oestrogen
Testosterone
