What is the Difference Between Germplasm and Somatoplasm

The main difference between germplasm and somatoplasm is that germplasm is the protoplasm of the germ cells whereas somatoplasm is the protoplasm of the somatic cells or body cells.

Germplasm and somatoplasm are two types of protoplasms with different characteristics. However, germplasm contains information about mRNA, proteins, and carbohydrates.

Key Areas Covered

1. What is Germplasm
   • Definition, Characteristics, Importance
2. What is Somatoplasm
   • Definition, Characteristics, Importance
3. Similarities Between Germplasm and Somatoplasm
   • Outline of Common Features
4. Difference Between Germplasm and Somatoplasm
   • Comparison of Key Differences               

Key Terms

Germplasm, Somatoplasm

What is Germplasm

Germplasm refers to seeds, plants, or plant parts that are useful in crop breeding, research, or conservation.  Germplasm also refers to the plants, seeds, or cultures that are maintained for the purposes of studying, managing, or using genetic information. They are available in seed collections stored in seed banks, trees growing in nurseries, animal breeding lines maintained in animal breeding programs or gene banks, etc. Therefore, the main feature of germplasm is that it carries the genetic information of a particular organism. Moreover, the hereditary material in the germplasm pass from generation to generation.

Figure 1: Germplasm Bank

Furthermore, germplasm is the protoplasm of the germ cells including egg cells and sperm cells. Multicellular organisms undergo sexual reproduction by producing germ cells in order to create offspring. Germ cells only occur in the reproductive organs of multicellular organisms. During sexual reproduction, germplasm undergoes meiosis.

What is Somatoplasm

Somatoplasm is the protoplasm of somatic cells. Usually, somatic cells are the cells in the body other than a gamete, germ cell, gametocyte, or undifferentiated stem cell. Somatic cells undergo sexual reproduction and divide by mitotic cell divisions. Since somatic cells do not produce any kinds of gametes, the information in the somatic cells such as the information about proteins, mRNA, and carbohydrates is not inherited. Mitosis produces two identical copies of somatic cells. In addition, in humans, somatic cells are diploid, containing two sets of homologous chromosomes. However, germs cells of humans are haploid, containing a single set of heritable chromosomes.

Figure 2: Germplasm develops into Somatic Cells

Furthermore, somatic cells originate from stem cells in the embryo. The functions of the differentiated somatic cells can be completely different from each other. The human body contains around three trillion somatic cells. They differentiate into neuron cells, blood cells, muscle cells, liver cells, etc. Neurons come together to form the nervous system. Blood cells are a part of the cardiovascular system. Cells like liver cells and stomach cells participate in the formation of the digestive system.

Similarities Between Germplasm and Somatoplasm

• Germplasm and somatoplasm are two types of protoplasm obtained from cells.
• Both contain a nucleus and therefore, they carry genetic information.
• Moreover, they are preserved by cryopreservation.

Difference Between Germplasm and Somatoplasm

Definition

Germplasm refers to the protoplasm of the germ cells while somatoplasm refers to the protoplasm of the body cells.

Contain

Germplasm contains genetic material that passes from generation to generation while somatoplasm contains information about proteins, mRNA, and carbohydrates.  

Ploidy

Germplasm is haploid while somatoplasm is diploid.

Mortality

Germplasm is immortal while somatoplasm is mortal and forms in every generation.

Variations

Variations of the germplasm are inherited while variations are not inherited in somatoplasm.

Examples

Moreover, the protoplasm of egg cells and sperm cells is an example of germplasm while the protoplasm of somatic cells of the body is an example of somatoplasm.

Conclusion

In brief, germplasm is the protoplasm of the germ cells: egg cells and sperm cells. In contrast, somatoplasm is the protoplasm of the somatic cells. However, germ cells undergo meiosis and somatic cells undergo mitosis. Therefore, germplasm contains a haploid number of chromosomes while somatoplasm contains a diploid number of chromosomes. On the other hand, the genetic changes of the germplasm are inherited. However, the main difference between germplasm and somatoplasm is the type of cells.

References:

1. National Research Council (US) Committee on Managing Global Genetic Resources: Agricultural Imperatives. Managing Global Genetic Resources: The U.S. National Plant Germplasm System. Washington (DC): National Academies Press (US); 1991. 1, Managing Crop Genetic Resources.

Image Courtesy:

1. “INTA – Banco de germoplasma” By National Agricultural Technology Institute – Own Work (CC BY-SA 4.0) via Commons Wikimedia
2. “Weismann’s Germ Plasm ” By Ian Alexander – Own Work (CC BY-SA 4.0) via Commons Wikimedia