Biology

In multicellular organisms, the G1 phase of the cell cycle can be influenced by A.external signals and the environment. These factors include:

1.Growth factors: Signals from nearby cells or tissues that promote cell division.

2.Nutrient availability: The presence of necessary resources like energy and raw materials for growth.

3.Cell-to-cell communication: Interactions with neighboring cells that can either promote or inhibit cell cycle progression (e.g., contact inhibition).

4.Hormones and signaling molecules: Signals from other parts of the organism can regulate whether a cell proceeds through G1.

These signals help determine whether the cell is ready to enter the S...