Indicate true (T) and false (F) statements below regarding s…

Indicate true (T) and false (F) statements below regarding signaling. Your answer would be a four-letter string composed of letters T and F only, e.g. TTTF. (  ) Since multicellularity evolved before the divergence of the plant and animal lineages, plants have homologs of most animal signaling proteins, such as nuclear receptors, Ras, JAK, and Notch. (  ) Receptor tyrosine kinases are the largest class of cell-surface receptors in plant cells. (  ) Animals use cyclic GMP, NO, and Ca2+ for cell signaling. (  ) Receptor tyrosine kinases are the most abundant type of receptors signaling proliferation in animal cells.

Arabidopsis thaliana seedlings show positive phototropism: t…

Arabidopsis thaliana seedlings show positive phototropism: they bend and grow toward the source of (blue) light. However, phototropism is not observed if the seedlings are treated with an auxin efflux inhibitor called NPA. Knowing that auxin stimulates elongation of the cells in the growing shoot, these observations are consistent with a model in which, in the presence of a lateral light, …