Main Difference – Cytoplasm vs Nucleoplasm
Cytoplasm and nucleoplasm are universal features of a eukaryotic cell. Cytoplasm is the sap enclosed by the cell membrane. Nucleoplasm is the sap enclosed by the nuclear envelope. Though the cytoplasm is found in each known cell, nucleoplasm is only found in eukaryotic cells. The main difference between cytoplasm and nucleoplasm is that cytoplasm is a fluid mass of the cell which is composed of cell organelles whereas nucleoplasm is the sap of the nucleus which contains the nucleolus.
This article looks at,
1. What is Cytoplasm
– Definition, Physical Nature, Function
2. What is Nucleoplasm
– Definition, Physical Nature, Function
3. What is the difference between Cytoplasm and Nucleoplasm
What is Cytoplasm
Cytoplasm is the fluid mass inside the cell, excluding the nucleus. In eukaryotic cells, cytoplasm is composed of cytosol and cells’ organelles. The cytosol is a gel-like substance which is enclosed by the cell membrane. Organelles are the membrane-bound, internal structures of a eukaryotic cell. Prokaryotes do not have a nucleus. Therefore, prokaryotic genetic material is also contained in the cytoplasm. Moreover, prokaryotic cells also lack other membrane-bound organelles. Thus, all metabolites are dissolved in the cytoplasm and all cellular reactions, such as protein synthesis and respiration occur in the cytoplasm of prokaryotic cells.
Physical Nature of Cytoplasm
The cytoplasm is composed of 80% water and it is usually colorless. It consists of two sections, endoplasm, the concentrated inner area and the ectoplasm, the outer layer. The ectoplasm is also called the cell cortex. After the exclusion of cell organelles and particles, the remaining of the cytoplasm is referred to as the groundplasm. It is called the hyaloplasm under the light microscope. The groundplasm is a highly complex polyphasic system. All cytoplasmic elements and large organelles such as mitochondria and chloroplast are suspended in the groundplasm.
Functions of Cytoplasm
Cytoplasm is composed of three components: cytosol, organelles, and inclusions. The cytosol or the groundplasm consists of dissolved molecules, cytoskeleton filaments, and water. Macromolecular crowding occurs due to the presence of the cytoskeleton filaments. Dissolved macromolecules are concentrated in particular areas within the cytoplasm, which is known as crowding. Interactions between the components in the cytoplasm are decided by the crowding.
Membrane-bound organelles are suspended in the cytosol such as nucleus, mitochondria, endoplasmic reticulum, Golgi apparatus, chloroplast, vacuole, and lysosomes. The generalized diagram of organelles suspended in the cytoplasm is shown in figure 1. Small particles such as calcium oxalate, starch, glycogen and lipid droplets are suspended in the cytoplasm as inclusions.
Figure 1:
Organelles Suspended in the Cytoplasm
Most cellular functions like metabolic pathways, including glycolysis, translation of mRNAs and the processes like cell division occur within the cytoplasm. The flow of the components throughout the cell is maintained by the permeability of the cytoplasm. The permeability is required by cellular functions like cell signaling, which requires diffusion of signaling molecules across the cell. Calcium ions, which are required for cell signaling and metabolic processes, move in and out of the cytoplasm.
In plants, the cytoplasmic movements around their vacuoles is referred to as the cytoplasmic streaming.
What is Nucleoplasm
The sap inside the nucleus is referred to as nucleoplasm. The nucleoplasm is also known as karyoplasm and nucleus sap. Nucleoplasm is enclosed by the nuclear envelop, which is a double-membrane structure. The nucleoplasm in the nucleus is shown in figure 2.
Figure 2: Nucleoplasm in the Nucleus
Physical Nature of Nucleoplasm
Nucleosol is the soluble liquid portion in the nucleoplasm. The nucleosol is also called the nuclear hyaloplasm. It is a highly gelatinous sticky liquid which supports the chromatin and nucleolus. Nucleoplasm is made up mostly of water and a mixture of various molecules and dissolved ions.
Functions of Nucleoplasm
Chromatin and nucleolus are suspended in the nucleoplasm. Nucleoplasm maintains the shape and structure of the nucleus. Nucleotide precursors and the enzymes, which are required for the activities that take place in the nucleus are contained in the nucleoplasm. Nucleoplasm contains the enzymes required by DNA replication and transcription. Post-transcriptional modifications of the mRNA, and ribosome biogenesis also occur in the nucleoplasm. Nucleoplasm maintains the transportation of materials required by the cell metabolism and function. Modified mRNAs are exported from the nucleus to the cytoplasm.
Difference Between Cytoplasm and Nucleoplasm
Localization
Cytoplasm: Cytoplasm is found inside the cell.
Nucleoplasm: Nucleoplasm is found inside the nucleus.
Enclosed by
Cytoplasm: Cytoplasm is enclosed by the cell membrane.
Nucleoplasm: Nucleoplasm is enclosed by the nuclear envelope.
Structure
Cytoplasm: Cytoplasm is a gelatinous structure.
Nucleoplasm: Nucleoplasm is a highly gelatinous structure compared to the cytoplasm.
Suspending
Cytoplasm: Organelles and inclusions are suspended.
Nucleoplasm: Sub-organelles called nucleolus and chromatin are suspended in the nucleoplasm.
Universality
Cytoplasm: Cytoplasm is a universal feature of all known cells.
Nucleoplasm: Nucleoplasm is only contained by eukaryotic cells.
Cell Division
Cytoplasm: The cytoplasm is divided into two cells during cytokinesis.
Nucleoplasm: The nucleoplasm is released during the nuclear division and refilled after the formation of the nuclear envelope.
Conclusion
The composition of cytoplasm and nucleoplasm is different from each other. Cytoplasm is composed of suspended, membrane-bound organelles and inclusions. Nucleoplasm lacks membrane-bound organelles but still bears the nucleolus. Chromatin is born by the nucleoplasm. The nucleoplasm is released and refilled during the cell division. Within the cytoplasm, enzymetic reactions such as the conversion of glucose into pyruvate in the glycolysis take place. Ribosome biogenesis and post-transcriptional modifications in the mRNA occur in the nucleoplasm. This is the main difference between cytoplasm and nucleoplasm.
Reference:
1.“Cytoplasm”. Wikipedia, the free encyclopedia, 2017. Accessed 28 Feb 2017.
2.“Cytoplasm”. TutorVista.com, 2017. Accessed 28 Feb 2017.
3.“Nucleoplasm”. Wikipedia, the free encyclopedia, 2016 . Accessed 28 Feb 2017.
4.“Nucleoplasm Function”. MEDICAL Dictionary, 2017. Accessed 28 Feb 2017 .
5.“Nucleoplasm”. Plant life, 2017. Accessed 28 Feb 2017.
Image Courtesy:
1. “Eukaryotic Cell (animal)” By Mediran – Own work (CC BY-SA 3.0) via Commons Wikimedia
2. “Figure 04 03 04” By CNX OpenStax – http://cnx.org/contents/[email protected]:rZudN6XP@2/Introduction, (CC BY 4.0) via Commons Wikimedia
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