Module 4
1. Module 4
1.6. Page 3
Module 4—From Fertilization to Birth
Reflect and Connect
You have read and viewed the many changes that occur throughout embryonic development. Before beginning your lesson assessment, you may choose to practice the review questions on page 518. Your teacher may indicate a selection of questions that would best suit your needs. Discuss your responses with your teacher.
Module 4: Lesson 1 Assignment
Retrieve the copy of the Module 4: Lesson 1 Assignment that you saved to your computer earlier in this lesson. Complete Reflect and Connect. Save your completed assignment in your course folder. You will receive instructions on when to submit your assignment to your teacher later in this lesson.
Reflect on the Big Picture
No other human growth period shows as much change as that of embryonic development. Understanding what is happening during pregnancy makes most expectant mothers and fathers very aware of the significance of the day-to-day changes and the factors that can affect these changes.
Fertility Case Study Update
So it was with Jane and John. However, when their twins were born, it took a bit more understanding to figure out how their twins could be born with different skin colours. The explanation comes from their parental background. John is of mixed race, and has a Jamaican-English heritage. Jane is of caucasian-Scandinavian background. John’s sperm carry genes for both light and dark skin colour.
José and Maria’s situation was more complicated and had severe results. Maria’s ectopic pregnancy progressed to a point that the Fallopian tube ruptured. The pregnancy was terminated and her seriously damaged tube was removed in surgery. During the surgery, doctors discovered that Maria only had one ovary and one Fallopian tube. The ectopic pregnancy had destroyed Maria’s only oviduct.
Going Beyond
The development of the embryo is very complex and consists of much more detail than can be presented in this lesson. Remember that all parts of the embryo, and later the fetus, develop from one cell. As cells divide and the organism grows, the cells differentiate and congregate to form all of the specialized structures of the body. If you are interested in this field of study, research how specific structures, such as the eyes, ears, muscles, or bones, are formed.
There are many other terms that define specific processes occurring during embryonic development. You may choose to research the meaning of the following terms:
- organogenesis
- neurogenesis
- angiogenesis
- chondrogenesis
- myogenesis
- osteogenesis
- zygocity
- fourth germ layer
You may also wish to research the Carnegie stages of development, in which each stage is defined through the embryo’s external and internal development. Your research could include how embryonic cells communicate to each other.
Module 4: Lesson 1 Assignment
Submit your completed Module 4: Lesson 1 Assignment to your teacher for assessment.