Tomorrow's Course (Probably)

Monday~ Monday~ Welcome back to Monday !!! Say hello to Mr. Monday~

Yesterday I had a graduate party in my department, maybe I'll post about it later. But first I 'll post about my prediction (#ngeh). Yes, like just I said before and it also written in the tittle. Tonight I 'll post about tomorrow's course. Tomorrow I will have 'animal's development' course. So lets get start !

Embryology was the formal term that used to explain a progressive development in organism. That term have different meaning in each animal classes. For the example, amphibian used that term from the fertilization until it has metamorphosed. Another example, Aves use the term until the eggs hatched (since Aves won't metamorphosed).

Basically there is two of old scientist's arguments about embryology.

Karl Ernst von Baer's Law

"Very simple but little difficult to be memorized"

1. General characteristics of the group to which an embryo belongs develop before special characteristics.
2. General structural relations are likewise formed before the most specific appear.
3. The form of any given embryo does not converge upon other definite forms but, on the contrary, separates itself from them.
4. Fundamentally, the embryo of a higher animal form never resembles the adult of another animal form, such as one less evolved, but only its embryo. 

Cell Lineage Mechanism

Pangenesis (Darwin)

Genetic material named 'Gemulla' formed by somatic cell which transmigrated into gammete cell (generative part of human cell).

Germplasm(Weissmann)

Germplasms is a collection of genetic resources (genetical unit) for an organism. Somatic cell are the result of differentiation process from gamete cells.

Period of embryonic development

1. Preparation stage

gamete cell's development in the gonads

2. Fertilization stage

fusion of male gamete cell (sperm) and female gamete cell (ovum)

3. Cementation stage

Division of the cell without significant growth, producing a cluster of cells that is the same size as the original zygote, is called cleavage. At least four initial cell divisions occur, resulting in a dense ball of at least sixteen cells called the morula. The different cells derived from cleavage, up to the blastula stage, are called blastomeres. The cleavage can be total (holoblastic) or partial (meroblastic) depending on the amount of yolk.

4. Cell shell formation 

 

Ectoderm - Nervous system, skin, organ on the entire surface of the skin, etc

Mesoderm - Bone, Muscle, Blood, Blood vessel, gamete cell, etc

Endoderm - Digestive cell, respiratory cell, lung, etc 

5.  Organogenesis
Each cell shell will a complex system that consist of cells with similar characteristic

6. Growth and Differentiation
Cell will growth and differentiate by it function.

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Thank you for reading my post. See yaa next time, fellas ^_^