Final answer:
An animal cell that cannot produce GTP would not be able to activate G-proteins, leading to a disruption in GTP-dependent signaling pathways.
Step-by-step explanation:
For an animal cell that lacks the ability to produce GTP, the correct answer is that it would not be able to activate G-proteins. G-proteins require GTP to become active, and without it, the signal transduction pathways that involve G-proteins would be disrupted. G-proteins are pivotal in many cellular processes, and their activation is crucial for the proper functioning of a range of physiological responses. In G-protein signaling, once a ligand binds to the receptor, a G-protein binds GTP and then activates other proteins in the cell, such as adenylyl cyclase, starting the signaling cascade. If a cell cannot produce GTP, this means that key signaling pathways and cellular responses would be inhibited, as G-proteins can not use ATP as an alternative to GTP.