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)

Explain monosaccharides, Monosaccharides :- Sugars consisting of  a  sin...

Monosaccharides :- Sugars consisting of  a  single  polyhydroxy  aldehyde or ketone unit.

Explain food plan for an anaemic pregnant lady, Explain Food plan for an an...

Explain Food plan for an anaemic pregnant lady? Justification of the Plan: The plan is for an anaemic pregnant lady, from a lower socio-economic level and doing moderate lev

Determine the categories of Taxonomic breakdown, For convenience, living th...

For convenience, living things are placed into different groups. Taxonomic breakdown of living things comprises the following categories: Family, Class, Genus, Phylum, Order, K

Bacteria, wine turns sour beause of the action of which bacteria? aerobic o...

wine turns sour beause of the action of which bacteria? aerobic or anerobic?

Determine the number average molecular weight of bag, 1.  You have two bags...

1.  You have two bags of polymer. Bag A has 10 kgs of polymer with weight average molecular weight of 336.6 kg and Bag B has 20kg of polymer with weight average molecular weight 39

Instrument examination and care, Instrument Examination and Care Cleani...

Instrument Examination and Care Cleaning instruments, provides a good opportunity to examine, replace or remove damaged instruments; lubricate items such as handpieces; and oth

Mention the role o ribosome in peptide, Mention the role o ribosome's in pe...

Mention the role o ribosome's in peptide -bond formation .How does ATP facilitate it? a) Of springs derived by asexual reproduction are known as clones. Justify giving two R

Preparation of the standard curve for haemoglobin, Preparation of the stand...

Preparation of the standard curve for haemoglobin? Label 6 clean dry rest tubes and label them as S1 -S6 Add 5 ml of Drabkin's solution to test tube numbers S2 - S6

Botany, cellular endosperm diagrammatic view

cellular endosperm diagrammatic view

What is nucleus where it is found, What is nucleus where it is found? ...

What is nucleus where it is found? Nucleus :  The nucleus is present only in eukaryotic cells. It is the control center and is generally found in the center of the cell. The

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