Mating and fertilisation, Biology

Assignment Help:

Mating and Fertilisation

In all animals sperms are motile and have to move and seek the eggs to fertilise them. For this an aqueous environment is necessary. This need of a liquid medium has led to two basic mating patterns.

1. External fertilisation - mating partners come in close proximity in water and concurrently shed their eggs and sperms in water.

2 Internal fertilisation - mating partners come into physical contact and copulate, in which the male transfers the sperms directly into the reproductive ducts of the female. The ova coming down the ducts obtain fertilized. Internal fertilisation is characteristic of terrestrial animals, but as well occurs in several aquatic forms. Internal fertilisation usually leads to development of an intromittent organ or penis in the male partner. A range of such copulatory organs are found in non-chordates, such as like dates there are spermathecae for storing sperms received during mating. As the eggs pass down the ducts sperms are released from the spermathaca to feitilise them. Honey bee queen mates just one time when it receives enough sperms to fertilise the many thousands of eggs she is going to lay in 4-5 years of reproductive life.


Related Discussions:- Mating and fertilisation

Define about the radiant energy - carcinogenic, Define about the Radiant En...

Define about the Radiant Energy? Radiant Energy: Radiant energy whether in the form of the ultraviolet rays of sunlight or as ionizing electromagnetic and particulate radiation

Determine the part of an actuating signal, Which of the following serves as...

Which of the following serves as an actuating signal, or as part of an actuating signal, in a negative feedback system? A. Action potentials in diaphragm skeletal muscle fibers

Explain bond specificity, Bond specificity Some  enzymes  act  on  a pa...

Bond specificity Some  enzymes  act  on  a particular  bond  (glycosidic,  peptide,  ester  etc.). Examples:  pepsin,  trypsin,  chymotrypsin  etc. are  all  only  acting  on

Metazoa, Metazoa In the two kingdom classification, the unicellular 'a...

Metazoa In the two kingdom classification, the unicellular 'animals' used to be clubbed together under a single phylum Protozoa that constituted sub-kingdom - Protozoa. The re

Developmental disorders, DEVELOPMENTAL DISORDERS - 1 .      AMNIONITI...

DEVELOPMENTAL DISORDERS - 1 .      AMNIONITIS- Inflammation of amnion due to infection. 2 .      ABORTION- Escape of a embryo prior to the stage of viability (ab

Dna replication, DNA Replication Deoxyribonucleic acid (DNA) is the car...

DNA Replication Deoxyribonucleic acid (DNA) is the carrier of genetic data for all living creatures. An organism's genome, made of DNA, encodes the genetic blueprint for buildi

How can a child become infected with gonorrhoea, How can a baby become infe...

How can a baby become infected with (a) gonorrhoea, (b) syphilis   (a)  During birth, a baby might be become infected with gonorrhoea bacteria as it passes by t

Types of ecosystem, Types of Ecosystem Basically ecosystems are of two ...

Types of Ecosystem Basically ecosystems are of two types : terrestrial and aquatic. If you travel from plains to the mountains in the Himalayas, you notice significant changes

Which substance starts clotting in humans after a wound, When a wound occur...

When a wound occurs in humans, platelets in the blood activate a substance that starts clotting process. The substance which starts clotting is: a) Adenosine (pron: ah-den-ah-s

Michaelis menten, Regulation of enzymatic action equations for competitive,...

Regulation of enzymatic action equations for competitive, non-competitive, uncompetitive inhibition and mixed reaction

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