Fertilisation, Biology

Assignment Help:

Fertilisation:

  1. Fertilisation is the process of fusion of male and female gametes. For fusion of male and female gametes, pollen grains have to reach the surface of the stigma.
  2. Pollen grains received by stigma germinate and give rise to pollen tubes. Only one pollen tube finally reaches the embryosac.
  3. This tube will have 2 male nuclei, which migrate to the tip of pollen tube at the time of fertilisation.
  4. One male gamete approaches the egg and fuses with egg to form a diploid (2n) zygote. This is first fertilisation.
  5. The other male gamete reaches the secondary nucleus and fuses with it to form endosperm nucleus which will be triploid (3n). This is second fertilisation in embryosac.
  6. In this way, diploid zygote is formed by union of male and female gametes in embryosac of ovary and triploid (3n) endosperm nucleus is also formed during fertilisation. With this fertilisation is completed.

2457_Fertilisation.png


Related Discussions:- Fertilisation

Food-borne zoonoses, Food-borne zoonoses Food-borne illnesses are seri...

Food-borne zoonoses Food-borne illnesses are serious public health problem. They are associated with the ingestion of contaminated foods by microorganisms and their toxins, ma

Carbohydrates requirement in pectic ulcer, Q. Carbohydrates requirement in ...

Q. Carbohydrates requirement in pectic ulcer? Carbohydrates: These should provide around 55 to 65% of the daily intake. Emphasis - J should be laid on the consumption of 60th s

Four characteristics of an efficient respiratory surface, State four charac...

State four characteristics of an efficient respiratory surface. Four characteristics of an well-organized respiratory surface are: a) thin epithelium, b) large surface ar

Carbomedics valve-types of valves, Carbomedics Valve :  Almost simila...

Carbomedics Valve :  Almost similar to StJude Medical valve, his is a low profile bileaflet valve made of pyrolitic carbon. On echo cardiography four small jets of regurg

Explain defensive proteins, Explain Defensive Proteins These proteins p...

Explain Defensive Proteins These proteins protect against diseases. Antibodies are the example of defensive proteins. These  combat bacteria and viruses. Also, immunoglobulins,

Effect of water pollution, (i) Effect of Human Health: (a) Mercury co...

(i) Effect of Human Health: (a) Mercury compounds in waste water in converted into methyl mercury by Bacterial action which causes numbness of limbs, lips and tongue, deaf

Isolating mechanism, In this section we are to discuss the means by which p...

In this section we are to discuss the means by which populations get separated or isolated from each other, first gain the status of'Sub-species and finally evolve mechanisms which

Nutrition of embryo - in vivo studies, Nutrition of Embryo - In Vivo Studie...

Nutrition of Embryo - In Vivo Studies The young proembryo derives its nutrition from ovular tissues with the help of suspensor. As the embryo develops its suspensor degenerate

What is the quaternary structure of a protein, What is the quaternary struc...

What is the quaternary structure of a protein? Do all proteins have quaternary structure? The quaternary protein structure is the spatial conformation because of interactions b

An alpha helix can be used to cross a membrane, An alpha helix can be used ...

An alpha helix can be used to cross a membrane What property do you think is common to all transmembrane regions?

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