The study of the development of an embryo from fertilisation to the embryo being described as a foetus.
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2answers
49 views
Which X-Y chromosomes have the developmental genes for mammals?
I know that for a given mammal, half the chromosomes come from father and half from mother. This is typically denoted as x-y. I've recently read about "toolkit" genes that control how a cell develops ...
5
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2answers
86 views
What metabolic activities are performed by a developing human fetus's liver?
I understand that organ function varies with the stages of development. Does a fetal liver EVER perform lipogenesis, gluconeogenesis, make bile, etc? Or does it only begin performing these actions ...
4
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1answer
111 views
Why are eggs “egg” shaped?
Is there a reason as to why chickens lay "egg" shaped eggs, as opposed to spherically shaped eggs (or a random shape)? <--- Main Question
For extra points (actually just to add more words in ...
2
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3answers
63 views
Simulating Cell differentiation
I'm a computer programmer deeply interested in Biology.
I wish to write a computer simulation for cell differentiation. I understand there will be seemingly impossible challenges in doing this. But ...
5
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1answer
85 views
What is the total number of rounds of cleavage during mammalian embryonic development?
That for frog is 12, but what about mammalian embryos?
I cannot find the exact number anywhere.
10
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1answer
177 views
Could a fetus properly develop in micro/zero-gravity?
I suppose another way of looking at the question is: how important is gravity for the development of mammal fetuses?
And if things would go wrong, what sort of things would they be, and what would be ...
8
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1answer
636 views
What determines testosterone exposure in womb, baby's genetics or mom's body?
I read this article which has the following quote:
The ratio between index and ring finger is believed to be linked to exposure to the male hormone testosterone in the womb.
And I wonder what ...
5
votes
2answers
510 views
Fetal development, gastrulation and embryonic disc
I completely confused by the images circulating on the internet of human gastrulation.
First, lets see how it happens in deuterostomes. This image depicts the process:
(image is from Wikipedia)
...
12
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2answers
434 views
Impact of Alan Turing's approach to morphogenesis
Shortly before his untimely passing, the computing pioneer Alan Turing published his most cited paper The Chemical Basis of Morphogenesis (1952).
The central question for Turing was: how does a ...
8
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2answers
157 views
Do twins “run in the family”?
My wife and I recently found out that we are going to have twins and so nearly everyone asks if we have a family history of twins. Now I know that the answer for me is that it doesn't matter—as ...
25
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3answers
921 views
Why is polyploidy lethal for some organisms while for others is not?
Polyploidy is the multiplication of number of chromosomal sets from 2n to 3n (triploidy), 4n (tetraploidy) and so on. It is quite common in plants, for example many crops like wheat or Brassica forms. ...
2
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1answer
101 views
Why are Birds and Reptiles with abundant yolk sac polyspermic?
I was given an explanation that birds and reptiles are polyspermic because they have an abundant yolk sac. But how does it explain the thing?
Chicken as an adult is not using in my opinion yolk as an ...
4
votes
1answer
880 views
What are differences between formation of embryonic disc in chick and mammal embryo?
Exam question which got lowest average points in my university: 1/5 average.
No markscheme available so my attempt below.
I assume that embryonic disk prefers to germ disk such that Formation prefers ...
10
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2answers
195 views
Why do pandas have a high probability of giving birth to twins?
According to the BBC documentary "Wild About Pandas", about half of panda birth result in twins. Why do they have such a high probability compared to other mammals? What factor(s) control that ...
6
votes
1answer
308 views
What forms the human amniotic sac?
I am trying to understand the formation of embryonic disc for human and chick so the following question is related to here about formation of embryonic disc.
I had thought that the amniotic sac forms ...
3
votes
1answer
168 views
Does chicken embryo form the disc called “discoblast” in the cleavage and blastulation of chicken?
This thread is related to my previous thread which is still unsolved mainly. I need to be able to compare chick and human cleavage and blastulation of zygote.
My friend says that
Chicken have ...
3
votes
1answer
200 views
Where does meiosis II of oogenesis end exactly in tuba uterina - uterus?
I know that metaphase II ends at ampulla tuba uterina, but I am not completely sure where the telophase II ends. Is it in the triangular section of cervix uterii?
I just have an intuition that the ...
4
votes
1answer
979 views
Do humans have Coelom?
Kimball Biology 5e says
Coelom is the main body cavity of many animals. It is lined with an epithelium derived from mesoderm.
Gilbert Embryonal Biology 9e says
Coelom is the space between ...
5
votes
1answer
116 views
When does Coelom form exactly?
Related to my other question.
I know that the coelom is derived from mesoderm.
Coelom seems to form during organogenesis within 3rd and 8th week of embryogenesis.
However, that answer is not either ...
