What is the Difference Between Plasmodial and Cellular Slime Molds

The main difference between plasmodial and cellular slime molds is that the plasmodial slime molds or the acellular slime molds are the bags of cytoplasm with thousands of individual nuclei, whereas the cellular slime molds live most of their lives as unicellular protists. Furthermore, plasmodial slime molds live in a ‘supercell’ while cellular slime molds cluster in response to chemical signals. Moreover, Myxomycophyta is the example of plasmodial or acellular slime molds while Acrasiomycota is the example of cellular slime molds. 

Plasmodial and cellular slime molds are the two types of slime molds of the older classification. Generally, slime molds are organisms with characteristics of both protists and fungi. 

Key Areas Covered 

1. What are Plasmodial Slime Molds
     – Definition, Characteristics, Importance
2. What are Cellular Slime Molds
     – Definition, Characteristics, Importance
3. What are the Similarities Between Plasmodial and Cellular Slime Molds
     – Outline of Common Features
4. What is the Difference Between Plasmodial and Cellular Slime Molds
     – Comparison of Key Differences

Key Terms 

Acellular Slime Molds, Cellular Slime Molds, Plasmodial Slime Molds, Plasmodium, Pseudoplasmodium, SuperCell

What are Plasmodial Slime Molds 

Plasmodial slime molds or the acellular slime molds are one of the two types of slime molds based on the older classification. Generally, the main characteristic feature of these slime molds is the presence of a large, multinucleated cell known as the ‘supercell’. Also, this stage is the plasmodium form with thousands of nuclei. For instance, this stage forms through the fusion of individual flagellated cells. Also, the nuclei of the plasmodium form are diploid. 

Figure 1: Plasmodial Slime Molds – Fuligo septica

Furthermore, this plasmodium of the plasmodial slime molds gives rise to a fruiting body, which undergoes meiosis to form haploid spores. Significantly, these spores produce flagellated gametes, which ultimately fuse to form a diploid zygote. Later, the zygote undergoes mitotic divisions without the division of the cytoplasm, resulting in a single cell that is large. 

What are Cellular Slime Molds 

Cellular slime molds are the second type of slime molds of the older classification. However, the main characteristic feature of cellular slime molds is that they spend most of their life cycle as separate single cells that are ameboid. Still, in response to a chemicals signal, these individual cells aggregate, forming swarms. Also, the multicellular slug, which forms as a result of this aggregation, is known as the pseudoplasmodia. 

Figure 2: Cellular Slime Molds Life Cycle

Moreover, the uninucleate cell stage of the cellular slime molds is the haploid stage. However, through the formation of the pseudoplasmodium, they enter into the asexual reproductive stage. Also, this pseudoplasmodium forms a stalked fruiting body in which spores are produced.  

Similarities Between Plasmodial and Cellular Slime Molds 

• Plasmodial and cellular slime molds are the two types of slime molds based on the older classification. 
• Both belong to the Kingdom Protista. 
• They have characteristics of both protists and fungi. 

Difference Between Plasmodial and Cellular Slime Molds 

Definition 

Plasmodial or acellular slime molds refers to the slime molds enclosed within a single membrane without walls and is one large cell, while the cellular slime molds refer to the slime molds that exist in their vegetative form as uninucleate ameboid cells. 

Significance 

Plasmodial slime molds are bags of cytoplasm with thousands of individual nuclei, forming a multinucleate plasmodium form, while the cellular slime molds live most of their lives as unicellular protists.  

Organization 

Plasmodial slime molds live in a ‘supercell’ while the cellular slime molds cluster in response to chemical signals.  

Somatic Phase 

The somatic phase of plasmodial slime molds is diploid while the somatic phase of cellular slime molds is haploid. 

Prior to the Formation of Sporangia 

No aggregation occurs prior to the formation of sporangia in plasmodial slime molds while cellular slime molds aggregate, forming a pseudoplasmodium before the formation of sporangia. 

Sporangium 

The sporangium of plasmodial slime molds is covered by peridium while the sporangium of cellular slime molds is naked. 

Capitalum 

Capitalum occurs inside the sporangium of plasmodial slime molds while capitalum is absent inside the sporangium of cellular slime molds. 

Meiosis 

Meiosis occurs inside the spores of plasmodial slime molds while meiosis does not occur inside the spores of cellular slime molds. 

Flagellated Stages  

Plasmodial slime molds have a flagellated stage in their life cycle while cellular slime molds do not have a flagellated stage. 

Examples 

Myxomycophyta is the example of plasmodial or acellular slime molds while Acrasiomycota is the example of cellular slime molds. 

Conclusion 

Plasmodial slime molds are the type of slime molds, containing a large cytoplasm and many nuclei called the ‘supercell’. Therefore, they exist in a multinucleated plasmodium stage. But, cellular slime molds are the second type of slime molds, existing in uninucleated forms, which cluster in response to a chemical response. Also, they exist in the haploid form while plasmodial slime molds occur in the diploid stage. Therefore, the main difference between plasmodial and cellular slime molds is their organization. 

References:

1. “PROTISTA TOPICS – Slime Molds.” SparkNotes, SparkNotes, Available Here.

Image Courtesy:

1. “Fuligo septica bl1” By Siga – Own work (Public Domain) via Commons Wikimedia   
2. “Figure 23 03 19” By CNX OpenStax (CC BY 4.0) via Commons Wikimedia