Gprotein-coupled receptors and receptor tyrosine kinases are both largely conserved mechanisms of cell communication. what scientific question is valid to ask when investigating the similarities between these two receptors to understand common mechanisms from which the two may have evolved? how did phosphorylation first begin as a way of modulating protein activity? how early in evolution did cells start using atp-to-adp conversion for energy to transduce signals? how has simple diffusion across a membrane remained a signal transduction mechanism? what factors lead to the ability to use cell energy for dimerization?

Four types of motile cells in human body?

Populations of blue-winged warblers, a type of bird, migrate south in the winter and return to canadian breeding grounds in the spring. as global temperatures have increased due to climate change, spring has started arriving in the warbler's breeding grounds earlier in the year, before the warblers return. warblers now arrive at their breeding grounds too late to select ideal nesting sites and to feed on important early-spring food sources how are populations of blue-winged warblers most likely to be affected by the earlier arrival of spring? o a. populations will go extinct since the warblers will stop migrating to breeding grounds. b. populations will be unaffected since most species can quickly adapt to effects of climate change. c. populations will increase since warmer temperatures are generally beneficial to survival, d. populations will decline since individuals will be less likely to successfully reproduce, reset next

9. wind power creates pollution. water air soil noise