Chapter 51 Lecture Enrichment Ideas
Describe how cellular differentiation occurs as different genes are turned on and off, and how different proteins and enzymatic products are produced in the different types of cells; review the differences in various kinds of tissues and discuss how dissimilar cells could come from a single zygote.
Illustrate how the cleavage process can go through many rounds of cell division with no cell growth, starting with the egg as the largest single cell in a species. Describe how differentiation may begin with the first cell division.
Examine why you could consider the yolk of an egg to be a single cell but why that really is not a reasonable conclusion, since the majority of the yolk is simply nutrient material used as the cellular part of the yolk that goes through cell division to form an embryonic plate that will develop into a chick.
Emphasize how a chick embryo has requirements other than the nutrients in the yolk and how they are dealt with—such as oxygen requirements (enters the shell) and removal of wastes (accumulate as uric acid in one of the extraembryonic membranes and are discarded with the eggshell).
Discuss how amniotic fluid is used to examine a fetus for genetic defects, since cells of the fetus are shed from the skin and from the respiratory and urinary tracts into the fluid. Also discuss how chorionic villi can be sampled in prenatal diagnosis.
Back to Lecture Enrichment Ideas