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

Production diseases, Pr o d u c t i o n Diseases The production...

Pr o d u c t i o n Diseases The production diseases, which were previously referred as metabolic diseases, include diseases like parturient paresis (milk fever), downer

Define functions of calcium in human body, Define Functions of Calcium in H...

Define Functions of Calcium in Human Body? Calcium salts provide rigidity to the skeleton and calcium ions play a role in many if not most, metabolic processes. In the vertebra

In which area lengthening of long bones occurs, Lengthening of long bones i...

Lengthening of long bones in humans takes place in a specific area of the bone. This area is known as the: a) Cancellous bone b) Medullary canal c) Periosteum (pron: per-

Hypocoagulation disorder and vitamin k deficiency, Which of the following p...

Which of the following patients likely faces the highest risk of an acquired hypocoagulation disorder and vitamin K deficiency? Answer A. A patient who is immunocompromised as a re

Tertiary prevention -community mental health programme, Tertiary Prevention...

Tertiary Prevention: In tertiary prevention, emphasis is placed on reducing disability resulting from illness. Tertiary prevention often means long term care. Disability may r

How b and t cells recognize antigen are true explain, Which of the followin...

Which of the following statements about how B and T cells recognize antigen are true? a. B cells only recognize antigen presented by class I or class II MHC molecules. b. Both cell

Nutrient intake during constipation, Q. What about the fluid and other nutr...

Q. What about the fluid and other nutrient intake during constipation? The fluid intake should be at least 2 litres daily. This includes fluid as foods and beverage besides wa

What is insect killing jar, Insect killing jar Secure a wide-mouth glas...

Insect killing jar Secure a wide-mouth glass jar with a screw top or single which closes very tightly. Place a wad of cotton in the bottom and cover it with a round piece of ca

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