Q1. What kind of cell communication is said to ovvur if the cell sevretes the growth factor that then acts on neighbouring cells to cause them to proliferate?

Q2. Testosterone and estrdiol are male and female sex hormones, respectively, in many vertebrates. In what ways do these molecules be different?

Q3. Illustrate the process of diffusion. Name and explain the condition that exists when the diffusion of a particular substance is complete.