Second stage of invagination, Biology

Assignment Help:

Second Stage of Invagination

The 2nd stage of invagination starts with release of secondary mesenchyme from the tip of archenteron into the blastocoel. The cells of secondary mesenchyme stay in which they are released at the tip of archenteron but their filopodia extend up to and attach to the inner side of the wall of blastocoel opposite to blastopore. Contractions of these ' filopodia pull the archenteron in the direction of the animal pole causing further invagination of the endoderm. Finally, the archenteron bends and its tip fuse along with the blastocoel wall on the ventral side where the mouth opens later. The secondary mesenchyme then disperses in the blastocoel and gives increment to mesodermal organs.


Related Discussions:- Second stage of invagination

Endocrine system, Endocrine System The nervous system brings about in...

Endocrine System The nervous system brings about integration and co-ordination of several activities of the animal. The afferent stimuli from several sense organs are brought

What are the properties of aqueous solutions, Which of the following is TRU...

Which of the following is TRUE about the properties of aqueous solutions? Select one: a. A pH change from 5.0 to 6.0 reflects an increase in the hydroxide ion concentration (

Explain atp molecules in photophosphorylation, Q. How is photic energy abso...

Q. How is photic energy absorbed by chlorophyll transfered to ATP molecules in photophosphorylation and How will be the resulting ATP used? Light excites energizes and chloroph

Explain the food digestion in protozoans, In some protozoans, food is alway...

In some protozoans, food is always ingested at the same place on cell surface, cytostome (cell mouth). Undigested food is removed at a cytoproct, or cell anus. All of this is simil

Compare the time-course to the rising phase, Assume you are injecting a sub...

Assume you are injecting a sub threshold depolarizing current step into a neuron. Draw the corresponding membrane voltage response; be sure to indicate the shape of the voltage cha

Is there respiratory pigment in the annelid blood, Q. Is there respiratory ...

Q. Is there respiratory pigment in the annelid blood? The blood in beings of the phylum Annelida contains the respiratory pigment hemoglobin the same found in chordates and oth

Coelomoducts of molluscs, Coelomoducts of Molluscs In Molluscs, like ...

Coelomoducts of Molluscs In Molluscs, like in Crustacea nephridia are absent. But certain of the larval pulmonates do possess protonephridia suggesting that they have been se

Discuss mental nerve and its anatomic variation, Discuss mental nerve, its ...

Discuss mental nerve, its anatomic variation and surgical importance. Mental nerve, branch of inferior alveolar nerve is a very important landmark during osteotomy procedures.

Which pathways produce atp via slp, How substrate-level phosphorylation (SL...

How substrate-level phosphorylation (SLP) differs from oxidative phosphorylation. Which pathways produce ATP via SLP? Where in cell oxidative phosphorylation (prokaryotes/eukaryote

Define about the metabolism of selenium compounds, Define about the Metabol...

Define about the Metabolism of Selenium compounds? Selenium compounds' are generally very efficiently absorbed by humans and selenium absorption does not appear to be' under ho

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