Which of the following processes is affected by the amount of yolk present in an embryo?Multiple choice question.MitosisOrganogenesisMeiosisGastrulation

Step 1: Break Down the Problem

To answer the question, we need to identify which of the listed processes is influenced by the amount of yolk present in an embryo.

Step 2: Relevant Concepts

1. Mitosis: The process of cell division that results in two genetically identical daughter cells. The amount of yolk does not significantly impact this process.
2. Organogenesis: The formation of organs during embryonic development. It can be influenced by yolk, but to a lesser extent than gastrulation.
3. Meiosis: The cell division that produces gametes (sperm and eggs). The amount of yolk is not a factor in this process.
4. Gastrulation: A phase early in embryonic development where the single-layered blastula reorganizes into a multilayered structure. The presence and amount of yolk significantly affect how cells migrate and differentiate during this critical phase of development.

Step 3: Analysis and Detail

• During gastrulation, the amount of yolk affects the dynamics of cell movement and segregation. For example, in animals with a lot of yolk (like in birds), gastrulation is altered due to the physical presence of the embryo's nutrient reserves.
• The shape and distribution of yolk can lead to different types of gastrulation, such as involution or invagination, impacting subsequent development significantly.

Step 4: Verify and Summarize

From the analysis, we can conclude that the most affected process by the amount of yolk present in an embryo is gastrulation. This phase is crucial for the spatial organization of cells that leads to the formation of various tissues and organs.

Final Answer

The process affected by the amount of yolk present in an embryo is Gastrulation.