Following statements are regarding to receptor serine kinases.

A. The two serines in each Smad3 that were phosphorylated by the RI receptor kinase bind to phosphoserine-binding sites in the MH1 domains of a Smad3 or a Smad4, forming a stable complex containing two molecules of phosphorylated Smad3 (or Smad2) and one molecule of the co-Smad (Smad4).

B. The bound importin then mediates translocation of the heteromeric R-Smad/co-Smad complex into the nucleus.

C. After importin dissociates inside the nucleus, the Smad3/Smad4 (or Smad2/Smad4) complex binds to other transcription factors to activate transcription of specific target genes.

D. Transcription of the PAI-1 gene requires formation of a complex of the transcription factor TFE3 with the R-Smad/co-Smad (Smad3/Smad4) complex and binding of all these proteins to specific sequences within the regulatory region of the PAI-1 gene.

E. Within the nucleus, R-Smads are further modified by phosphorylation of their linker domains, monoubiquitinylation of their MH1 domains, acetylation of their MH2 domains, and dephosphorylation of the C-terminal serines by nuclear phosphatases.

Which of the following combination is incorrect?

#Question id: 3273

#Unit 11. Evolution and Behavior

The number of forward mutations is equal to the number of reverse mutations then

a) Population is in equilibrium for forward and reverse mutation rates

b) The population is being in Hardy–Weinberg equilibrium

c) No further change in allelic frequency

#Question id: 3276

#Unit 11. Evolution and Behavior

Which of these conditions are always true of populations evolving due to natural selection?

Condition 1: The population must vary in traits that are heritable.

Condition 2: Some heritable traits must increase reproductive success.

Condition 3: Individuals pass on most traits that they acquire during their lifetime.

#Question id: 3277

#Unit 11. Evolution and Behavior

Which of the following describes the most likely order of events in allopatric speciation?

#Question id: 3278

#Unit 11. Evolution and Behavior

What does the biological species concept use as the primary criterion for determining species boundaries?

#Question id: 3279

#Unit 11. Evolution and Behavior

Which two of the following have operated to increase divergence between mosquito fish populations on island?

a. improved gene flow

b. bottleneck effect

c. sexual selection

d. founder effect

e. natural selection

#Question id: 3280

#Unit 11. Evolution and Behavior

Small populations are threatened by the loss of genetic diversity from

a. Inbreeding

b. Genetic drift

c. Limited mating