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Cytoplasmic Polarity in Embryonic Cell Development

APBIO-VGGKFB

Two key factors affect the genetic expression that ultimately determines an embryonic cell’s fate, cytoplasmic segregation and external induction of neighboring stem cells.

Cytoplasmic segregation, specifically, relies on microtubule organizing centers to establish polarity in a developing cell. Polarity can be described as the unequal distribution of cytoplasmic determinants in order to create two distinct ends of a cell. This is especially significant to the integrity of nuclear division, induction proximity, and stem cell proliferation.

Consider what these cytoplasmic determinants might be.

Which of the following materials inside a cell are going to experience routine spatial change through normal cell development and physiology?​

A

While organelles remain permanently fixed in the cytoplasm, the molecules involved in protein synthesis are always mobile, such as mRNA and proteins.

B

Motility of a cell’s organelles, mRNA and proteins remains fluid while a cell carries out its varied functions, depending on the support and fluctuations of its cytoskeleton.

C

Larger organelles, such as the endoplasmic reticulum network do not suspend as well as smaller sized organelles in the cytoplasm, and therefore, do not make adjustments once they have been formed in an embryonic cell.

D

Due to shared chemical behaviors, only membrane-enclosed organelles gain microtubule mobility inside a cell.