The key difference between mosaic and regulative development is that mosaic development is an embryo development category classically associated with invertebrates while regulative development is an embryo development category classically associated with vertebrates.
The embryo development is broadly divided into two categories based on classical studies of experimental embryology. They are mosaic development associated with invertebrates and regulative associated with vertebrates. The development of all embryos involves a combination of both mechanisms.
CONTENTS
1. Overview and Key Difference
2. What is Mosaic Development
3. What is Regulative Development
4. Similarities – Mosaic and Regulative Development
5. Mosaic vs. Regulative Development in Tabular Form
6. FAQ – Mosaic and Regulative Development
7. Summary – Mosaic vs. Regulative Development
What is Mosaic Development?
Mosaic development is a type of embryo development classically associated with invertebrates. If the embryo development is mosaic type, the development is exclusively controlled by cytoplasmic determinants. In this mechanism, the fate of all would mainly depend uniquely on its lineage. The position of the cells in the embryo would be totally irrelevant when deciding the fate of the cells.
Figure 01: Mosaic Development
Moreover, in a mosaic embryo, the fate of the cells is governed entirely by its intrinsic characteristics such as cytoplasmic determinants the cells inherit at cell division. In mosaic embryo development, each cell undergoes autonomous specification. In this scenario, if the cells are removed from the embryo, they develop according to their intrinsic instructions and differentiate into the appropriate part of the embryo even though the rest of the embryo is not present.
What is Regulative Development?
Regulative development is a type of embryo development classically associated with vertebrates. Inductive signals exclusively control the regulative development. The fate of the cell would depend mostly on its position in the embryo.
Figure 02: Mosaic vs Regulative Development
Moreover, in regulative development, the fate of the cell is governed by its interactions with other cells. In regulative development, each cell undergoes conditional specification. Therefore, if the cells are removed from the embryo, they will not fulfill their normal fate due to the lack of necessary cell interactions.
What are the Similarities Between Mosaic and Regulative Development?
- Mosaic and regulative development are two different types of embryo development mechanisms.
- The development of all embryos involves a combination of both mechanisms.
- Both these mechanisms are mainly discussed in development biology.
- They are extremely important for the survival of different species.
What is the Difference Between Mosaic and Regulative Development?
Mosaic development is an embryo development category classically associated with invertebrates, while regulative development is an embryo development category classically associated with vertebrates. Thus, this is the key difference between mosaic and regulative development. Furthermore, in mosaic development, the position of cells in the embryo is entirely irrelevant when determining the fate of the cells. On the other hand, in regulative development, the position of cells in the embryo is crucial when determining the fate of the cells.
The infographic below presents the differences between mosaic and regulative development in tabular form for side-by-side comparison.
FAQ: Mosaic and Regulative Development
What is a mosaic egg in developmental biology?
In developmental biology, a mosaic egg refers to an egg with cytoplasmic determinants that unevenly distribute during cell division, determining the fate of cells based on their intrinsic factors rather than interactions with neighboring cells.
What is mosaic cleavage?
Mosaic cleavage is a type of embryonic cell division where the fate of each cell is determined by the localized substances present in the egg rather than by interactions between cells.
What is an example of a regulative egg?
An example of a regulative egg is the sea urchin egg.
Summary – Mosaic vs. Regulative Development
In humans, the embryo begins to develop about four days after an egg is fertilized. Initially, embryonic development begins as a tiny mass of cells, which eventually gives rise to the human form. Mosaic and regulative development are two different types of embryo development mechanisms. Mosaic development is classically associated with invertebrates, while regulative development is classically associated with vertebrates. Furthermore, mosaic development is controlled by cytoplasmic determinants, whereas inductive signals control regulative development. Hence, this summarizes the difference between mosaic and regulative development.
Reference:
1. “Mosaic and Regulative Development: Two Faces of One Coin.” Cell Press.
2. “Introduction to Development.” Columbia Education.
Image Courtesy:
1. “The effect of cell mixing during development on the number of corneal epithelial stripes in an adult mosaic eye” By Mort RL, Ramaesh T, Kleinjan DA, Morley SD, West JD – Mosaic analysis of stem cell function and wound healing in the mouse corneal epithelium (CC BY 2.0) via Commons Wikimedia
2. “Schémamosaique” By MarilouD – Own work (CC BY-SA 4.0) via Commons Wikimedia