Pre-embryo - human development, Biology

Assignment Help:

Pre-Embryo - Human Development

About thirty hours after fertilization the zygote goes through mitosis giving rise to 2 blastomeres. These blastomeres go through further cleavages and by the 3rd day after fertilization, the tiny mass of cells reaches the uterus. Through this time it is a solid ball of cells called morula. In the next three days the morula is changed into a hollow ball of cells called blastocyst. The cavity of blastocyst is filled along with fluid secreted by the cells. One portion of the blastocyst consists of a concentrated mass of cells that will give rise to the entire body of the new individual. This is termed as the inner cell mass (ICM). Interestingly, each cell of this mass has the capability to develop into a complete individual. Identical twins are formed if the ICM splits. The outer ring of cells of the blastocyst surrounding its cavity is termed as trophoblast and gives rise to all the extra-embryonic membranes including much more of the placenta. This stage of development is important as the cells begin to move for the first time and become rearranged to shape the new individual. This procedure you might recall is the beginning of morphogenesis. However the major morphogenetic events occur during the third to eighth week.


Related Discussions:- Pre-embryo - human development

What is phylum porifera in classification of the animal king, What is Phylu...

What is Phylum Porifera in Classification of the Animal King? Sponges are the simplest form of animals. Their bodies are not organized in any specific pattern other than masses

Explain the chemical properties of milk, Explain the chemical properties of...

Explain the chemical properties of milk Autoclaving milk, wherein temperature of around 121 o C is achieved, causes browning. The brown colour is due to the heat effecting an i

Indicate the probability of producing, I have no idea how to do this: two g...

I have no idea how to do this: two gene loci, A and B, assort independently, and alleles A and B are dominant over alleles a and b. Indicate the probability of producing: an AB phe

Edema, Ed e m a It refers to excessive accumulation of fluid in tiss...

Ed e m a It refers to excessive accumulation of fluid in tissue spaces caused by disturbance in the fluid interchange between capillaries, tissue spaces and lymphatic vessel

Malpighian tubules, Malpighian Tubules Other arthropods like insects ...

Malpighian Tubules Other arthropods like insects and myriapods and arachnids have Malpighian tubules, the outgrowths of alimentary canal like excretory organs. Malpighian tub

Gel electrophore, How can you see a DNA by size if it too small to see wit...

How can you see a DNA by size if it too small to see with a microscope

Tuberculosis, Tuberculosis Tuberculosis is caused by a Bacillus-myco...

Tuberculosis Tuberculosis is caused by a Bacillus-mycobacterium tuberculosis, a gram- positive and acid-fast organism. It is communicable disease. Mode of Transmissio

Write the meaning of polyuria, Q. Write the meaning of Polyuria? Increa...

Q. Write the meaning of Polyuria? Increased Urine (Polyuria): When sugar is increased in the blood it is filtered from the body along with the water. This is the reason for fre

Cell membrane, CELL MEMBRANE As discrete units of life  all living cell...

CELL MEMBRANE As discrete units of life  all living cells are separated from each other and from their external environment by an  extremely delicate (75 A to 100 a= 0.00075 to

Define methods for estimation of iron and haemoglobin, Define Methods for E...

Define Methods for Estimation of Iron and Haemoglobin? In this section we shall study the procedure involved in estimation of iron in any sample first followed by a review on t

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