ABIO303: Experimental Approaches

What did the frog-salamander transplant experiments demonstrate?

- They showed that inductive interactions are species-specific and depend on the competence of the responding tissue.

- Example: Frog optic cup can induce a lens only if the salamander ectoderm is competent to respond.

What did Saunders' regional mesenchyme-epidermis experiments prove?

- They demonstrated regional specificity in epithelial-mesenchymal interactions.

- The type of structure formed (e.g., feathers, scales, hair) depends on the mesenchyme's regional identity, not the epidermis.

What was the purpose of Bindin-coated bead experiments?

→ They tested species-specific sperm-egg recognition in sea urchins.

→ Bindin-coated beads agglutinate only with eggs of the same species, confirming Bindin-receptor specificity in fertilization.

What do these experiments collectively demonstrate?

→ That cell-cell signaling, competence, and specificity are crucial for developmental induction and recognition across species.