Testes (testicles), Biology

Assignment Help:

TESTES (TESTICLES) -

  1. 2 in number (Diarchic). Pinkish in colour. Oval shaped.
  2. 4-5 cms long, 2.5 cm wide and 3 cm thick. Mesodermal.
  3. In embryonic stage attached to kidney by mesorchium membrane.
  4. In embryo at 7th month of division descend down in scrotel sac. Condition is extra abdominal, due to it 3°C less temperature is available, helpful in spermatogenesis.
  5. Both scrotel sac internally separated by septum scroti. External by a scar-like raphe.
  6. In scrotel sac fat layer is absent, involuntary muscles are dertos tunic present.
  7. Lumen of scrotel sac is vaginal coelome, in it testes present.
  8. Vaginal coelome is connected to main coelome by inguinal canal.
  9. In some cases testes do not descend down in sac, condition is cryptorchidism such animals are high flankers (sperm are not produced)
  10. Testes is attached to pre position by spermatic cord (gonadial artery, gonadial vein, nerve and connective tissue present).
  11. Testis is attached to wall of scrotel sac by elastic structure i.e. gubernaculum cordis.
  12. Unit of testis is seminiferous tubule where sperms are manufactured by spermatogenesis. All tubules form a cord of 200-400 meter. These tubules are spreaded in connective tissue.
  13. In tissue interstitial cells or cells of Leyding present. These cells secrete testastaron or androgen hormones to control secondary sexual characters.
  14. Outside each seminiferous tubule, tunica propria present. Inside it germinal epithelium or basement membrane present. Made up of cuboidal epithelium.
  15. Epithelium consists of P.G.C. and few sertoli cells.
  16. P.G.C. (Primordial germ cells) are endodermal in nature.
  17. P.G.C. are responsible for spermatogenesis.
  18. Different stages of formation of sperms can be seen as spermatogonia, primary spermatocyte, sec. spermatocyte, spermatid and sperms.
  19. Sertoli cells or nurse cells or sustentacular cells are nourishing cells i.e. provide glycogen as food to develope sperms. So sperm's head is embeded in sertoli cells.
  20. Around testes, testicular capsule present made up of 2 layers.
  21. Outer is tunica vaginalis & inner is tunica albuginea.
  22. From tunica albuginea straight vertical spetum mediastinum is originated from it septula testes are given out to form 200-300 compartments.
  23. In each compartment seminiferous tubule present.
  24. On tunica albuginea, mediastinum & septule testes, a membrane present rich in blood supply. This membrane is tunica vescularosa.
  25. Surgical removal of testes is orchidectomy & gonad is castration or gelding.

2406_testis.png 1933_testis1.png


Related Discussions:- Testes (testicles)

What is immuno adsorption, It is elimination of an antigen or antibody from...

It is elimination of an antigen or antibody from a sample by the process of adsorption, to which the complimentary antigen or antibody is bound.

Brackish water-marine water-types of water found on earth, Brackish Water ...

Brackish Water The content of dissolved salts in brackish water is higher than the fresh water and ranges between 0.5 to 35%. These waters of intermediate salinity range are d

How to ensure food safety by haccp, Ensuring  Food  Safety It is now w...

Ensuring  Food  Safety It is now well-known that the end product inspection and  testing does not provide safety of food. It has inherent limitation of mapping the potential ha

Mineral availability of organic mineral complexes, Mineral availability of ...

Mineral availability of organic mineral complexes A number of mineral chelates and complexes are available from a variety of manufacturers. A chelate is described as a metal c

Microorganisms on on basis of nutrient degradation capacity, Q. Microorgani...

Q. Microorganisms on On basis of nutrient degradation capacity? On basis of nutrient degradation capacity: - Proteolytic: Microorganisms, which are capable of protein degra

Fusion of sperm and egg, Fusion of Sperm and the Egg After the penetr...

Fusion of Sperm and the Egg After the penetration of the extracellular layers by sperm there occurs the fusion of the - sperm plasma membrane with that of the egg. In mammals

Explain delavirdine, Explain Delavirdine Delavirdine (DLV, Rescriptor)...

Explain Delavirdine Delavirdine (DLV, Rescriptor) - Delavirdine is the least potent NNRTI. A study comparing delavirdine/zidovudine/didanosine, delavirdine plus either zidovud

Regional specialisation, Regional Specialisation Regional specialisati...

Regional Specialisation Regional specialisation takes place usually by three processes – 1) Restriction of certain structures to a few segments, for example, gonads are res

What is respiratory system explain their functionality , What is Respirator...

What is Respiratory System explain their functionality ? The respiratory system is responsible for the transport of oxygen and carbon dioxide from outside the body to and from

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd