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#Question id: 31379


The cadherin catenin complex is extremely important during compaction from a morula to the blastula. Transition of early embryonic cells into a blastula differed depending on the presence or absence of calcium ions. In addition, an investigator blocked the expression of β-catenin using vivo morpholinos to detect its effect simultaneously on compaction. Which one of the following conditions will lead to the most successful transition of the morula into the blastula?



#Unit 5. Developmental Biology
  1. The blastula will continue to develop even when calcium ions are absent, since β-catenin will get activated automatically by cadherins.
  2. In the absence of calcium ions, calcium ionophores will assist development even when vivo morpholinos to β-catenin are introduced.
  3. Presence of calcium ions will enhance development when vivo morpholinos to cadherins have been introduced to the early embryo.
  4. Presence of calcium ions are essential for activation of cadherin and β- catenin, so that actin gets mobilized and compaction ensues.