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Facts about Cell Cytoplasm For Kids


The cytoplasm comprises cytosol – and the organelles – the cell’s internal sub-structures.The concentrated inner area is called the endoplasm and the outer layer is called the cell cortex or the ectoplasm.

  • It remains uncertain how the varied components of the cytoplasm interact to allow movement of particles and organelles while maintaining the cell’s structure.
  • An obvious example of such function is cell signalling, a process which is dependent on the manner in which signaling molecules are allowed to diffuse across the cell.
  • While small signaling molecules like calcium ions are able to diffuse with ease, larger molecules and subcellular structures often require aid in moving through the cytoplasm.
  • It is thought that the component molecules and structures of the cytoplasm behave at times like a disordered colloidal solution (sol) and at other times like an integrated network, forming a solid mass (gel).
  • This theory thus proposes that the cytoplasm exists in distinct fluid and solid phases depending on the level of interaction between cytoplasmic components, which may explain the differential dynamics of different particles observed moving through the cytoplasm.
  • Recently it has been proposed that the cytoplasm behaves like a glass-forming liquid approaching the glass transition.
  • In this theory, the greater the concentration of cytoplasmic components, the less the cytoplasm behaves like a liquid and the more it behaves as a solid glass, freezing larger cytoplasmic components in place.
  • A solid glass cytoplasm would freeze subcellular structures in place, preventing damage, while allowing the transmission of very small proteins and metabolites, helping to kickstart growth upon the cell’s revival from dormancy.
  • There has been research examining the motion of cytoplasmic particles independent of the nature of the cytoplasm.
  • The cytosol’s filaments include the protein filaments such as actin filaments and microtubules that make up the cytoskeleton, as well as soluble proteins and small structures such as ribosomes, proteasomes, and the mysterious vault complexes.
  • Organelles (literally “little organs”), are usually membrane-bound structures inside the cell that have specific functions.