Reаd Biоlоgy 2e, Chаpter 9 Cell Cоmmunicаtion, Section 9.1 (reproduced below as well).Figure 9.8: 1) A receptor tyrosine kinase is an enzyme-linked receptor with a single helical transmembrane region and extracellular and intracellular domains. 2) Binding of a signaling molecule to the extracellular domain causes the receptor to dimerize. 3) Tyrosine residues on the intracellular domain are then autophosphorylated, 4) triggering a downstream cellular response. The signal is terminated by a phosphatase that removes the phosphates from the phosphotyrosine residues. Credit: Rao, A., Ryan, K., Tag, A., Fletcher, S., and Hawkins, A. Department of Biology, Texas A&M University.HER2 is a receptor tyrosine kinase. In 30 percent of human breast cancers, HER2 is permanently activated, resulting in unregulated cell division. Lapatinib, a drug used to treat breast cancer, inhibits HER2 receptor tyrosine kinase autophosphorylation (the process by which the receptor adds phosphates onto itself), thereby reducing tumor growth by 50 percent. Besides autophosphorylation, which of the following steps would be inhibited by Lapatinib? Select one option. Signaling molecule binding, dimerization, and the downstream cellular response.Dimerization and the downstream cellular response.The downstream cellular response.Phosphatase activity, dimerization, and the downstream cellular response.Written Explanation (≈100 words)Based on the knowledge you have acquired, please give a detailed explanation of why you chose your answer (100 words)Diagram (Hand-Drawn)Create a hand-drawn, labeled diagram of the HER2 signaling pathway. On your diagram, illustrate exactly where Lapatinib acts and clearly show the specific biochemical step that is inhibited. Your drawing must distinguish between the extracellular and intracellular environments to show why this specific step is blocked.