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1answer
2k 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 ...
4
votes
3answers
11k views

Does Human Female Meiosis II occur after fertilization with sperm?

I am reading the answer and I am getting confused by the sentence: At the end of meiosis I females have two daughter cells and meiosis II only occurs if and when fertilization occurs by a sperm ...
2
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1answer
475 views

What does entering of sex chromosomes to gametes mean during meiosis I?

I am reading one answer about meiosis: During meiosis I, the sex chromosomes separate and enter different sperm or egg cells (gametes). I assume that sex chromosomes refer here to homologous ...
1
vote
1answer
188 views

Is this mammalian embryo blastocyst, gastrula or only phase between them?

The picture shows the formation of early blastocyst and late blastocyst. The middle embryo has embryoblast. My professor says that blastocyst in general has embryoblast and trophoblast. Embryoblast ...
4
votes
1answer
365 views

Does Amphibian embryo's blastocoel become a primitive yolk sac without yolk?

The mammalian blastocoel becomes yolk sac without yolk according to my professor. I have not found any evidence that such a thing happens in amphibians like frog. I need to be able to compare and ...
5
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1answer
88 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.
4
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1answer
296 views

What is the largest perennial herbaceous plant?

What is the largest perennial herbaceous plant? My guess would be some kind of banana or bamboo.
7
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1answer
338 views

To understand why satellite cells are genetically inactive in Barr body

DAPI is used as a stain for DNA heterochromatic and euchromatic regions. The Barr body is heterochromatic. In the slide of a normal human female cheek's somatic cells, there is apparently no other ...
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votes
2answers
1k views

What is the Giemsa staining of chromosomes?

I got the question in my exam and wrote the following and I do not understand what is wrong in it: Giemsa staining is a staining method to stain particularly malaria and other parasital diseases. ...
2
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1answer
74 views

Substrates of cytochemical reactions in this immunostaining

Expression of extracellular protein Laminin 9 alpha-4 chain in human skeletal muscle. Indirect immunostaining with HRP immunostain marker. Ob.x40. I have unsuccessfully searched NCBI -database, JSTOR ...
17
votes
3answers
189 views

What is the optimal frame size for protein secondary structure prediction methods?

The whole question is What is the optimal frame size for the second and third generation protein secondary structure prediction methods? Justify your answer. I remember it has something to do ...