In an experiment on eye development, a thin piece of aluminum foil was placed between the bulging wall of the brain and the overlying ectoderm where the eye normally forms. Wherever the foil was placed, the lens failed to develop because the foil __________.

• A. changed the gravity in the region
• B. rearranged the cytoplasmic determinants in the adjacent cells
• C. prevented the cortical reaction
• D. prevented the acrosomal reaction
• E. prevented the inductive contact that normally stimulates the lens to form

Answer: (E)

Verified step by step guidance

1. Understand the context: The problem involves the development of the eye, specifically the formation of the lens, which is a process that involves interactions between different tissues.
2. Identify the key players: The bulging wall of the brain and the overlying ectoderm are involved in the development of the lens. These tissues interact through a process known as induction.
3. Define induction: Induction is a process where one group of cells influences the development of another group through direct contact or signaling molecules. In this case, the brain tissue induces the ectoderm to form the lens.
4. Analyze the role of the foil: The placement of aluminum foil between the brain and ectoderm physically blocks the contact necessary for induction. This prevents the signaling required for lens formation.
5. Conclude the effect: Since the foil prevents the inductive contact, the lens fails to develop. This highlights the importance of physical contact in the inductive process during eye development.