Morphogenesis is the totality of the developments of organs, organisms, or individual cell organelles. In humans, embryogenesis and fetogenesis are important aspects of morphogenesis.
What is morphogenesis?
Morphogenesis is the process by which living structures acquire their shape. In humans, morphogenesis is divided into embryogenesis and fetogenesis. In the context of morphogenesis, living structures acquire their shape. In humans, morphogenesis is divided into embryogenesis and fetogenesis. Morphogenesis is part of ontogenesis. Ontogenesis is the opposite of phylogenesis. Thus, it is not the phylum development that is important here, but the development of the individual being. The morphogenetic development includes all stages of the living being. It begins with the germ development and reaches up to the completely developed living being. At the end of morphogenesis is the organism with its characteristic shape. Morphogenesis is the basis of developmental biology.
Function and task
Human morphogenesis is divided into embryogenesis and fetogenesis. Embryogenesis is the phase of embryonic development. It begins with the fertilization of the female egg and ends with the onset of fetogenesis. Embryogenesis is divided into a pre-embryonic phase and an embryonic phase. The pre-embryonic phase comprises the first three weeks of pregnancy. Here, the three germ layers named endoderm, mesoderm and ectoderm are formed. The development of the zygote into the blastocyte is also part of the pre-embryonic period. During this blastogenesis, the fused egg-seed cell becomes a fluid-filled cavity with pluripotent stem cells. In the embryonic phase, the embryonic anlagen of the organs are formed. This phase lasts from the fourth to the eighth week of pregnancy. However, embryogenesis can be divided not only into these two phases, but also with regard to individual organs and organ systems. Thus, embryonic head development, embryonic heart development and embryonic liver development are distinguished. The organ development in these phases is also called organogenesis. Embryogenesis is followed by fetogenesis. The organs that were created in embryogenesis continue to develop here. In addition, differentiation of the tissues takes place. The stage of fetogenesis begins with the 61st day of pregnancy and ends with birth. Fetogenesis is characterized by rapid body growth. The facial proportions of the unborn change, eyes and ears reach their final position. Arms and legs become longer and form proportionally. As early as the third month of pregnancy, this enables the unborn child to perform its first muscular activities. In the sixth month, the skin grows very strongly. Since the underlying fat layer does not grow as quickly, the fetus appears wrinkled. In the seventh month of pregnancy, morphogenesis of the lungs is complete. The unborn baby could now breathe on its own. Therefore, from this week on, premature babies are considered viable. The last months of pregnancy are all about growth. The morphogenesis of the vital organs comes to an end here. In the ninth month, the morphogenesis of the organs is finally completed. The unborn child also no longer grows significantly. It sinks deep into the mother’s pelvis and assumes its birth position. About 40 weeks after the first day of the last menstrual period, birth occurs.
Diseases and ailments
Disorders can occur at all stages of morphogenesis. Depending on the timing and severity, the consequences can be very diverse. Depending on the timing of the disruption, different disorders can be distinguished. Blastopathies are due to a disturbance of morphogenesis during blastogenesis, which occurs from embryonic day 1 to 18. Embryopathies are developmental disorders caused during the third to eighth embryonic week. Fetopathies are diseases of the fetus (foetus). Here, morphogenesis is affected from the ninth embryonic week. Possible causes for disorders of morphogenesis can be genetic or exogenous. Exogenous causes include certain medications, infectious diseases of the mother, maternal diabetes mellitus, and alcohol consumption by the mother. Alcohol in particular often severely damages the unborn child. Ethanol is a cell toxin and inhibits cell division. About one third of all children born to alcoholic women are born with alcohol embryopathy.Typical is a combination of short stature, mental developmental delay, a too small head and facial anomalies. This combination is also called fetal alcohol syndrome. Viruses or bacteria can also disrupt morphogenesis. During pregnancy, rubella disease in the mother can have severe consequences for the child. The viruses are transmitted via the placenta to the unborn child, where they impede cell divisions and cell differentiation. This results in either pregnancy abortion or rubella embryopathy. Embryopathy can cause various malformations. The central nervous system (CNS), the eyes and ears, and the heart are particularly affected. Brain inflammation, glaucoma, deafness or hearing loss, growth retardation, or congenital heart defects occur. A common symptom combination consists of deafness, lens opacity, and heart defects. Approximately 10% of infected newborns die as a result of the infection. Therapy is not possible after infection. Maternal vaccination protection should therefore be secured before a possible pregnancy. If a pregnancy is planned, the rubella titer should therefore be determined. If the protection is not sufficient, a booster vaccination can be given at an early stage. In the case of a pregnant woman, however, the vaccination should not be carried out. The unborn child could become infected with the vaccine virus.
