#Question id: 3483
#Unit 11. Evolution and Behavior
Which of the following statements about evolution of behavior is correct?
A) Natural selection will favor behavior that enhances survival and reproduction.
B) An animal may show behavior that maximizes reproductive fitness.
C) If a behavior is less than optimal, it is not completely evolved but will eventually,become optimal.
#Question id: 4139
#Unit 3. Fundamental Processes
Which one of the following statements about the elongation phase of protein synthesis is true?
#Question id: 10998
#Unit 7. System Physiology – Animal
When does the second heart sound occur in the ventricular pressure–volume relationship?
#Question id: 10160
#Unit 6. System Physiology – Plant
Which of the following statements about the C4 cycle is true ?
a.) C4 plants uses the enzyme phosphoenolpyruvate carboxylase (PEPCase), rather than rubisco
b.) Unlike rubisco, O2 does not compete with HCO3 − in the carboxylation catalyzed by PEPCase
c.) initial carboxylation catalyzes in bundle sheath cells, four-carbon acids formed and flow across the diffusion barrier to the mesophyll cells
d.) during decarboxylation, releasing CO2 that is refixed by rubisco via the Calvin–Benson cycle
#Question id: 1251
#Unit 4. Cell Communication and Cell Signaling
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?