Embryology
The term Embryology, in its widest sense, is applied to the various changes which take place during the growth of an animal from the egg to the adult condition: it is, however, usually restricted to the phenomena which occur before birth. Embryology may be studied from two aspects: that of ontogeny, which deals only with the development of the individual; and that of phylogeny, which concerns itself with the evolutionary history of the animal kingdom.
In vertebrate animals the development of a new being can only take place when a female germ cell or ovum has been fertilized by a male germ cell or spermatozoön. The ovum is a nucleated cell, and all the complicated changes by which the various tissues and organs of the body are formed from it, after it has been fertilized, are the result of two general processes, viz., segmentation and differentiation of cells. Thus, the fertilized ovum undergoes repeated segmentation into a number of cells which at first closely resemble one another, but are, sooner or later, differentiated into two groups:
(1) somatic cells, the function of which is to build up the various tissues of the body;
(2) germinal cells, which become imbedded in the sexual glands—the ovaries in the female and the testes in the male—and are destined for the perpetuation of the species.
Having regard to the main purpose of this work, it is impossible, in the space available in this section, to describe fully, or illustrate adequately, all the phenomena which occur in the different stages of the development of the human body. Only the principal facts are given, and the student is referred for further details to one or other of the text-books 1 on human embryology.
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The cell physiology – Cytoplasm
Depending on the cell that is, cytoplasm bears different names, thus:
- liquid phase of cytoplasm is called citosol
- located in the cytoplasm membrane or cortex called ectoplasma
- cytoplasm situated between the cortex and nuclear membrane called endoplasm
In the cytoplasm we find:
- nucleus (the largest organ common to all cells)
- common organic of all cells
- cell-specific [...]
The cell physiology – Membrane
The cell is morphologic and functional unit of the human body.
The cell is composed from: Membrane, Cytoplasm, Core, Cell Organic (common, specific).
Membrane cell: – Lipo-protein double layer : hydrophilic pole outward, inward hydrophobic pole
- contains protein molecules
- covered glicocalix
- Thickness of 7.5 to 10 nm
- Composition: 55% protein, 25% phospholipids, 13% cholesterol, other lipids and [...]
What is biotechnology?
Biotechnology, in its most general meaning, is the use of biologic processes to create a product for human use and benefit. Today, when people use the term biotechnology, we usually think they mean the application of modern methods of manipulation of DNA (deoxyribonucleic acid), the genetic information of an organism, to make a product. In [...]
Kidney System – The components
Anatomy and Phisology of kidney device
Urogenital device – it is formed from urinary and genital systems. The most part of excretion products are eliminated through an organs system called excretory system
Urinary tract – has 2 kidneys and exit ways of urin: potassium, basins, ureters, bladder and urethra.
Kidneys – secretory organs of urine, have grains and [...]
Accreditation Council for Continuing Medical Education
Since most of the hospitals or clinics out there are under the influence of an association I have decided it would be good to create a post for each association and to describe what that as. does.
Also, many doctors or nurses are part of groups or health association, but us, the people who are not [...]
My TOP 10 Health Quotes
Sometimes words can do miracles. In this domain, it is not all about body health but also about mental / psihical health. Self-suggestion will help you pass over hard times. Reading funny things and keeping your self active mentally means very much!
This is why I think it is nice, from time to time, to read [...]
Hello to health!
Welcome to out health blog! We want to help people reading this blog live a healthy life. Knowing what may or may not be a disease will help you educate your family also.
We will discuss on this blog many of the diseases that you may encounter quite often. We will also give suggestions regarding the [...]