Spermatophores, Biology

Assignment Help:

Spermatophores

Many non-chordates do not release free sperms during copulation. They have a mechanism to bundle and enclose a number of sperms in a sheath usually made of gelatinous material. Such bodies are called spermatophores. Most insects, the centipedes and certain molluscs produce spermatophores. Male centipede emits spermatophores and places it on a web already made. The female picks up the spermatophores and takes it into her genital opening. In many male cephalopods such as Loligo and Argonauta one of the arms gets specialised for the transfer of spermatophore into the females. Such an arm is called hectocotylized arm. The spermatophore, after having been deposited in the female, finally releases the sperms which move into the female ducts or the spermathaca.


Related Discussions:- Spermatophores

What is meant by bioassay, What is meant by bioassay? Name the two bio...

What is meant by bioassay? Name the two bioassays that are used to determine auxin activity in plants.

Describe the various types of rna, Describe the various types of RNA? ...

Describe the various types of RNA? Types of RNA :  There are three different types of RNA, all formed by transcription from DNA: (1) Messenger RNA (mRNA) is a single unc

What are the types of digestion, What are the types of digestion and of dig...

What are the types of digestion and of digestive system of platyhelminthes? Flatworms have incomplete digestive systems and they show intracellular and extracellular complement

What is the phase of the menstrual cycle, Q. In general what is the phase o...

Q. In general what is the phase of the menstrual cycle when copulation may lead to fecundation? Although this is not a rule, to be effective fecundation in general must occur w

Long-term responses - behaviour of plants, Long-term responses - Behaviour ...

Long-term responses - Behaviour of Plants Plants alter their course of development to suit the prevailing environmental conditions. For example, leaf maturation and fall, onse

Programmes directed towards the common crop plants, Programmes directed tow...

Programmes directed towards the common crop plants These programmes can be directed towards incorporating the following traits among common crop plants. Non-photo

Phosphorylation of glucose, Phosphorylation of  glucose Glucose is con...

Phosphorylation of  glucose Glucose is converted to  glucose-6-phosphate since phosphorylated  intermediates do not readily penetrate cell membrane and  this commits glucose  t

Explain assessment of iron status, Explain Assessment of Iron Status? I...

Explain Assessment of Iron Status? In view of widespread iron deficiency, it is important to have reliable and sensitive measures of iron status. Iron status can be assessed by

Zoonoses disease-ehrlichiosis, Ehrlichiosis The disease is caused by a ric...

Ehrlichiosis The disease is caused by a rickettisia, called Ehrlichia canis. Dogs and man are the reservoir hosts. The infection is transmitted through bite of infected tick, Rhip

What is parasitism, What is parasitism? Parasitism is the ecological in...

What is parasitism? Parasitism is the ecological interaction in which a being lives at the expense of another. The parasite often does not cause immediate death of the host sin

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