Spermatogenesis-Male Anatomy
Explain the term Spermatogenesis with the help of figure.
Expert
Take a look at the etymology of the title of this section – sperm + genesis – or creation of sperm! The testis is about 4 cm long by 2.5 cm wide in adult men and is covered by thin fibrous capsule. The interior is divided into compartments or lobules. It is composed of tightly packed coils of SEMINIFEROUS TUBULES which measure about 250 metres in length!
The entire inner surface of the seminiferous tubules is lined with SPERMATOGONIA which actually produce the sperm. Spermatogenesis can only occur at about 95’F or 35’C and internal body temperature is 98.6’F or 37’C. And here is something totally amazing – the scrotum can control its own temperature through the use of CREMASTER muscles which pull the scrotum closer to the body if they are cold so that the 35’C is maintained! Inside the testes the seminiferous tubules empty into the RETE TESTIS which in turn empties into the EPIDIDYMIS. This is another coiled tube that if uncoiled would stretch out to 6 ½ metres in length. The sperm spend about 10 days in the epididymis before they are mature enough to continue their journey. So although the sperm are produced in the testis – they mature in the epididymis where the acidic environment keeps the mature sperm inactive. Let’s return to how the sperm are produced. During spermatogenesis, spermatogonia divide to form SPERMACYTES – which then differentiate into SPERMATIDS which are immature sperm cells. In normal body process SOMATIC cells are produced which contain 46 chromosomes – spermatids are considered HAPLOIDS since they only contain 23 chromosomes or ½ of the male parent’s DNA. The whole process of spermatogenesis takes about 70 days and once mature the sperm can live several weeks inside the male. SERTOLI CELLS nourish the developing SPERMATIDS until they are mature and they provide a barrier between the blood and the seminiferous tubules. If immature sperm exit before they are mature they are useless. If also protects the sperm from the blood vessels which supply the necessary hormones and nutrients for growth – if this barrier gets damaged and the sperm enter the blood vessels the body senses it is a foreign object and will produce antibodies against its own sperm! (Another reason for infertility).
Elements of scientific management The main elements of scientific management are : i) work study involving work measurement and work improvement thr
Production Output: Production is an activity taken out under the control and accountability of an institutional unit which uses inputs of labor, goods and capital and services to generate goods and services. Production doesn’t cover purely natur
Briefly, explain regarding the foreignness of a molecule, that makes a substance antigenic?
Concerning solubility, how are lipids categorized?
Why is cytoplasm of sperm cells much decreased?
State some of the respective constituents of gray matter and of white matter of the spinal cord?
why are vaccines made of the own disease agent or of fragments of it?
In short range what will take place to the levels below and above a population of secondary consumers of the numeric pyramid if a high number of individuals from this population die?
Write down the phenomenon of apical dominance in the plants? How can it be artificially eliminated?
Advantages of Planning Planning helps the organization achieve its objectives early. In this way planning helps the organization in many ways. Some
18,76,764
1930239 Asked
3,689
Active Tutors
1457922
Questions Answered
Start Excelling in your courses, Ask an Expert and get answers for your homework and assignments!!