(A) Cells of early newt gastrula exhibit conditional development.
(B) Cells of early newt gastrula exhibit autonomous development
(C) Cells of late newt gastrula exhibit conditional development.
(D) Cells of late gastrula exhibit autonomous development.
The correct inferences are:
(1) (A) and (D) (2) (B) and (C)
(3) (A) only                                                (4) (D) only

In the study of developmental biology, the fate determination of embryonic cells at different stages provides crucial insight into how organisms form complex tissues and organs. Tissue transplantation experiments performed on newt embryos at various gastrula stages have demonstrated striking differences in cellular development patterns.

At the early gastrula stage in newts, cells exhibit conditional development. This means that cells retain developmental plasticity and their fate depends on their position and interactions with neighboring cells. In transplantation experiments, cells from an early gastrula, when moved to a different location, can alter their developmental fate to match the new environment. This shows that early gastrula cells are not yet fully committed to a specific fate.

In contrast, cells at the late gastrula stage show autonomous development. These cells are determined, having irreversibly committed to a specific developmental fate. When transplanted, late gastrula cells grow according to their original fate despite the new location, indicating independence from external signals.

Thus, the correct inferences drawn from these transplantation experiments are:

• (A) Cells of early newt gastrula exhibit conditional development.

• (D) Cells of late gastrula exhibit autonomous development.

This corresponds to option:

(1) (A) and (D)