Embryonic development is the process wherein a zygote forms and develops through four main stages: cleavage, patterning, differentiation, and growth. During these stages, the zygote divides, organizes cells into germ layers, specializes structures, and undergoes growth to form a fetus. The document also outlines key characteristics and developments that occur during each trimester of pregnancy.

1. Embryonic Development By Rachel F., Katelyn M., Marli M., and Katina R.

2. What is Embryonic Development? Embryonic Development is when the embryo is formed and develops. It starts with the fertilization of a egg, which after is called a zygote. The zygote goes through rapid divisions. The scientific name for it is Embryogenesis.

3. Stages of Embryonic Development Embryonic Development has 4 stages: Cleavage Patterning Differentiation Growth

4. Cleavage Cleavage is the first stage of embryonic development. In this stage the cell starts to divide. Each with the exact genes in the zygote. It is controlled by the mother’s genes. In the end of the process of Cleavage the zygote is now called a blastula.

5. The Different Stages of the Organism.

6. Patterning This is the second phase. During this phase the cells produced by Cleavage organize themselves in layers and masses. Parts of the organism that develop: Front and the rear. Back side and belly side. Left and right side. During this process three major germ layers are formed : Ectoderm Mesoderm Endoderm By the end of this process the zygote’s genes are expressed.

7. Differentiation This is the third stage. It starts to make specialized structures and has more functions. The body now produces neurons, skin cells, muscle cells and etc. The organized into tissues, the tissues organize into organs, and the organs into systems.

8. Growth This is the last stage. In this stage the organism goes through a period of growth. New cells are formed and more extra cellular matrix.

9. The First Trimester The first trimester is when the cell starts to divide. The zygote begins to develop. At the end of this trimester the: Head is round Eyes are closed Taste buds are forming The internal organs move into the body cavity Upper and lower limbs are formed.

10. The Second Trimester In the second trimester the baby is becoming more developed. The baby develops more. At the end of the trimester: The baby’s eyes are open. The sex is determined. The baby weighs 12.5 ounces. Bones and muscles are growing steadily.

11. The Third Trimester In the third trimester the baby is developing. What is developed: Footprints and fingerprints are formed Eyelids open and close Brain development grows rapidly The baby is born

12. The End