Page 1 - 2. Lesson notes-Development of embryo
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SAI International School
                                           Subject – Biology, Class-VIII
                                         Topic- Reproduction in animals
                                       Sub topic- Development of embryo
                                                       Module -29
                                                     Lesson notes



               Development of embryo

               The zygote divides repeatedly in oviduct and forms a ball of cells is called embryo. The
               cells are grouped in to different types of tissues.

               This developing embryo reaches uterus and gets embedded in its wall by a structure
               called placenta. The embryo receives nourishment from mother’s body through placenta
               and develops into a complete baby.


               The structure of embryo having all body parts or organs is called foetus.

               Zygote                          Embryo                          Foetus
               Has only one cell.              Have many cells.                Have many cells.
               No tissue differentiation is    Tissue differentiation is       Tissue differentiation is
               seen.                           seen.                           seen.
               Organs are not formed.          Organs are not formed.          Organs are formed.
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