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

Form of protozoan reproduction, Q. Which is the form of protozoan reproduct...

Q. Which is the form of protozoan reproduction that generates more variability? Sexual reproduction always generates extra genetic variability than asexual reproduction. That i

Define flow phase in physiological response to injury, Define Flow Phase in...

Define Flow Phase in Physiological Response to injury? It is characterized by hyper metabolism, increased cardiac output, increased urinary nitrogen losses, altered glucose met

Define vitamin a, Define Vitamin A, Iron and Zinc required for elderly? ...

Define Vitamin A, Iron and Zinc required for elderly? Vitamin A, Iron and Zinc: The recommendation for iron is said to decrease in elderly women. Intake of vitamin E and zinc

Explain the second maturation division of the mammalian ovum, The second ma...

The second maturation division of the mammalian ovum occurs: 1. Shortly after ovulation before the ovum makes entry into the Fallopian tube 2. Until after the ovum has been p

What is its function of pylorus, Q. What is the valve that separates the du...

Q. What is the valve that separates the duodenum from the stomach called? What is its function? The valve that separates the stomach from the duodenum is the pylorus it has the

Explain human development, Explain Human Development? Human development...

Explain Human Development? Human development begins with fertilization, and continues throughout life. Fertilization occurs when two sex cells, a sperm cell and an egg cell, jo

Name of structures you would expect to find in the dermis, Name of the stru...

Name of the structures you would expect to find in the dermis. In the dermis you would expect to search sensory nerve endings, nerve fibres, capillaries, arterioles and venules

Different modes of nutrition, Explain different modes nutrition like Autotr...

Explain different modes nutrition like Autotroph,hetrotroph,saprotroph,holozoic

Slight or no metamorphosis, Slight or no Metamorphosis In primitive w...

Slight or no Metamorphosis In primitive wingless insects (Apterygota) such as spring tails, silver fish etc. and in secondarily apterous insects the young ones which hatch fr

Infective endocarditis, Infective Endocarditis :  All patients with prosth...

Infective Endocarditis :  All patients with prosthetic valve come under the high-risk category for endocarditis. They need prophylactic antibiotics if any procedure, which is like

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