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Embryology is the study of embryo development in the uterus from the fertilization of the zygote to fetus growth in a period of nine months (38 weeks). Embryogenesis begins with the fusion of the male and female sex gamete, which then the parent cell is replicated to produce identical cells in mitosis - this forms a hollow ball structure called the blastula. The blastula is characterized as having an animal pole, where there are rapidly dividing cells and the vegetal pole that has slowly dividing cells. Then a blastocyst forms, which is an inner cell mass in the blastula.

Gastrulation is when the cells in the blastula migrate inwards, producing a pore that eventually becomes the anus – humans are classified as deuterostomes from this distinction. In gastrulation the blastula reorganizes itself to have three germ layers that encapsulate the blastopore: ectoderm, mesoderm and endoderm. In organogenesis these three layers develop into different organs systems, the ectoderm is the outer lining which forms the nervous system and skin. The mesoderm is the middle layer that produces the musculoskeletal and blood system, whilst the endoderm is the inner layer develops into the digestive organs, lungs and bladder. The next stage is neurulation, this is when the ectoderm folds itself to produce the notochord, which becomes the central nervous system (CNS).

There are many different terms used in embryology. Zygote is the initial diploid cell produced from the fusion of the male and female sex gametes, whilst the embryo is multi-cellular diploid mass that is embedded into the endometrium and undergoing stages of development. The embryo is then renamed ‘fetus’ during the ninth week of development. 

Biology Questions

* What is the story about the placenta and fetal development? * What is the role of immune cells in the body? How would you expect the body to respond to these foreign cells? what is the normal immune responses and propose an explanation for the lack of a normal immune response in the case of microchimerism elopement?

Genetics, embryology and Phenotype of Williams Syndrome

A summary of the embroyologically important genes that lead to Williams syndrome, a rare genetic disorder resulting in an elf-like appearance, and a "peaks and valley's" phenotype of perfect pitch, excellent verbal abilities, poor spatial ability and low IQ. William's syndrome is thought to be the origin of myths of fairies and

Embryology and Evolution

A. Describe how embryological similarities across vertebrate species give some evidence of those species having descended from a common ancestor. B. Describe how biochemical analyses have helped provide support for a generalized theory of evolution. Provide references

Undergraduate Embryology

Need an overview of the following topics: - Extraembryonic membranes and placentation - Digestive system - Development of nervous system

Embryology Topics

Information on Gametogenesis, reproductive organs and the sexual cycle, fertilization, cleavage and formation of the blastula, gastrulation and the establishing of germ layers.

Define Hox genes and its role in embryogensis.

A detailed description of Homeotic (Hox) genes and embryology. Complete with Collinear Characteristics, function and mechanism and regulation of Hox Genes. Tables and Diagrams depicting the Spatial and Temporal collinearity. Response in MS Word.