For growing it is critical to determine the spatial relationship between structures within the embryo. In the early stages of development of the organism is necessary to determine the relative orientation of a plurality of segments and organs of the body.For example, the direction of the head-tail is on the craniocaudal (more…)
When undifferentiated cell undergoes a process of differentiation, she makes a series of individual steps, showing different features or characteristics, until you reach your final objective (for example, when the cell precursor becomes a red blood cell, a keratinocyte, or a cardiomyocyte). In the developing body signs cells are different not (more…)
In the course of development, cells divide (reproduce), acquire new functions or structure (differencemode), move within the embryo (migrate) and undergo programmed death (often via apoptosis). These four major cellular process that act in different combinations and in different ways lead to growth and morphogenesis (literally “creation of form”), creating the (more…)
- Blastocyst – after morula stage of embryogenesis, when the cells of the morula secrete fluid and form a fluid-filled cavity in which is outlined a separate group of cells — the inner cell mass (embryoblast). The remaining cells of the blastocyst (trophoblast) form the chorion, part of the placenta and (more…)
Development is determined by genes that interact with cellular and environmental surroundings. Involved gene products include transcription regulators, factors of diffusion of interacting with cells and guides them along specific development pathways to receptors for such factors, structural proteins, intracellular signaling molecules and much more. Not surprisingly, the most numerous developmental (more…)
Malformations have many causes. Chromosomal abnormalities account for approximately 25% of all causes, of which the most common autosomal trisomy of chromosomes 21, 18 and 13.
Another 20% are caused by monogenic mutations. Some defects are inherited as autosomal dominant traits, such as achondroplasia or waardenburg syndrome. Nevertheless, the majority of heterozygotes (more…)
Developmental biology deals with the only thing uniting all the question: how a single cell can develop into a Mature organism? In humans, this conversion occurs whenever a single fertilized egg develops into a person with more than 1013-1014 cells, several hundred distinct cell types and dozens of fabrics. This process (more…)
In studies of birth defects clinical dysmorphology constantly confronted with the phenomenon of pleiotropy. Congenital defects are pleiotropy, when the only primary pathogen causes abnormalities in more than one organ system in different parts of the embryo or in multiple structures that arise at different times of fetal life. Agent responsible (more…)
Dysmorphology — study of congenital malformations, changing the form of one or more body parts of a newborn. The research objectives of the physician-dysmorphology — understand the contributions of abnormal genes and non-genetic environmental factors in the development of birth defects.
The application of genetics in medicine began in the early twentieth century with the understanding of Garrod and the other doctors that the laws of inheritance Mendel can explain the re-emergence of some diseases in families. Over the next 100 years, medical genetics has grown from a small section engaged in (more…)