Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Animals: Development Human embryonic development proceeds through different stages after fertilization Outline 1. Key concepts 2. Development of mature animal from zygote 3. Human embryonic development (zygote birth) A. Cleavage B. Gastrulation C. Organogenesis 4. Conclusions Key Concepts: 1. Human embryonic development proceeds through different stages after fertilization 2. Cleavage and cellular interaction helps cell differentiation and morphogenesis 3. In cell differentiation, a cell selectively uses certain genes and proteins not found in other cell types 4. Morphogenesis starts at gastrulation Development of mature animal from zygote A. Growth - mitosis B. Differentiation (specialized) – after specialized, cell can’t go back C. Morphogenesis (formation of shape) Human embryonic development A. Cleavage 1. Zygote divides without an increase in size 2. A solid round cell ball (morula) is formed 3. The morula develops a cavity blastocyst Formation of the Early Embryo Formation of the Early Embryo Cleavage Human embryonic development B. Gastrulation – blastocyst forms three germ layers 1. Ectoderm – epidermis of skin; lining of mouth and nose; hair; glands of skin (sweat, mammary); nervous system; lens of eye 2. Mesoderm – muscle; bone, skeleton; blood, circulatory system; gonads; kidney 3. Endoderm – lining of digestive and respiratory tracts; liver; pancreas Stages of Animal Development Cleavage Stages of Animal Development Morula Stages of Animal Development Gatrulation Primary tissues develop Stages of Animal Development Cell differentiation proceeds Gastrulation Human embryonic development C. Organogenesis – three germ layers develop to specialized organs or tissue types. - begins about the 15th day after fertilization. about the 18th day from fertilization nervous system first to begin development about 22nd day circulatory system – pump blood respiratory system - 23rd day excretory system – 25th day digestive system – 25th day reproductive system – 28th day Human embryonic development C. Organogenesis By 13 weeks – 1st trimester : fetus 9 cm (4 in.); 15 g (0.5OZ) all major organ systems start to function By 26 weeks – 2nd trimester : fetus 35 cm (14 in.); 1000 g (2.2 lb) By 38 weeks birth: baby 50 cm (20 in.); 3200 g (7 lb) Embryo at 4 Weeks Embryo at 5-6 Weeks Embryo to Fetal Period: Week 8 Fetus at 16 Weeks Embryonic Development Happy Birthday Development and Aging In Conclusion 1. An embryo cannot develop properly unless each stage of development is successfully completed 2. In cell differentiation, a cell selectively uses certain genes and proteins not found in other cell types 3. Morphogenesis starts at gastrulation Nothing in the world is more important than my baby rhino!