Defects in human development, Biology

Defects in Human Development

1) For instance, when a pregnant woman drinks alcohol her embryo is exposed to similar concentration of alcohol as is in her blood. The alcohol may generate a set of physical and mental abnormalities termed as foetal alcohol syndrome (FAS). In this syndrome prenatal and postnatal growth is retarded. Abnormal facial features, reduced head size and mental retardation are seen. As little as 8.5 ml of alcohol every day or engaging in a single drinking binge by a pregnant woman can result in FAS.

2) Infection through German measles (caused by Rubella virus) in a pregnant woman can cause congenital malformations in the embryo. If the rubella infection is contacted throughout the first four or five weeks of pregnancy, the embryo's eyes, ears and heart may be malformed when exposure to this virus during later stages of development may result in defects in the central nervous system.

3) There are several drugs that are apparently harmless to adults but may be injurious to developing embryos. They are not toxins but teratogens like they lead to malformations in the embryo. Perhaps the most unfortunate example of the effect of teratogens is the drug thalidomide which was used as a tranquilizer. In a couple of years of its introduction over 8000 crippled children with no limbs were take birth in Europe and England.

4) The highest sensitivity to such type of a teratogenic agents is during 18-55 days after conception. The peak period being day 30. Pregnant women must, therefore, never use any drugs without the advice of their attending physicians.

Posted Date: 2/1/2013 5:17:37 AM | Location : United States







Related Discussions:- Defects in human development, Assignment Help, Ask Question on Defects in human development, Get Answer, Expert's Help, Defects in human development Discussions

Write discussion on Defects in human development
Your posts are moderated
Related Questions
What are the main cellular features of fungi? There are unicellular and pluricellular fungi. All fungi are eukaryotes and heterotrophs. Fungi have cells with cell wall made

Q. What is the hormone secreted by the growing ovarian follicles? What is the action of that hormone upon the uterus? The follicles that are growing after menses secrete estrog

A protein is normally found completely within the inside of a lipid bilayer. The protein likely has: a) Mostly hydrophobic side chains, pointed outwards, with the peptide backbo

Feeding on Small Particles Microscopic algae and bacteria can be taken in directly into the cell by the digestive vacuoles. But one of the most successful methods of feeding o


Floral Induction The transformation of vegetative apex into a floral apex is a multifactor and multistep phenomenon. Despite researches on flowering carried out during the las

Is there a difference between the initial and the final energy levels in catalyzed and non-catalyzed reactions? The catalysis does not alter the energetic state of reagents and

Each gene has a characteristic mutation rate. Mutation rates are often described as an average per gene basis. For instance, Drosophila has one detectable mutation per 10,000 loci,


Biota of Littoral Zone This zone is the shore region of the marine ecosystems and is subject to violence of waves and tides, fluctuation of water level and variability of temp