What does the presence of external growth signals indicate about a cell?

The presence of external growth signals in a cell indicates that the cell is likely to support cell division. Growth signals, such as hormones and growth factors, interact with specific receptors on the cell's surface, initiating a series of internal pathways that promote cellular proliferation. These signals play a crucial role in normal cell cycle regulation, signaling the cell to move from the resting phase into the active phases of cell division.

When a cell receives these external signals, it can progress through the various stages of the cell cycle, preparing for mitosis and ultimately resulting in cell division. This process is essential for growth, tissue repair, and overall homeostasis in multicellular organisms. The ability to respond to growth signals is fundamental for cells that need to multiply, indicating their readiness for division.