What is the Difference in Alleles Between Parent Cell and Daughter Cells

The main difference in alleles between parent cell and daughter cells is that in mitosis, alleles of parent cell and daughter cells are genetically identical whereas, in meiosis, they are genetically different. That means; genetic recombination occurs through chromosomal crossing-over during meiosis. Furthermore, in mitosis, both parent cell and daughter cells contain the same amount of DNA while in meiosis, the daughter cells contain half of the amount of DNA of the parent cell.  

Alleles in parent cell and daughter cells are crucial for both sexual and the asexual reproduction. Their number and the genetic content are important either to maintain the same function as the parent cell or to serve as gametes. 

Key Areas Covered 

1. What are the Alleles in the Parent Cell
     – Definition, Chromosomes, Expression
2. What are the Alleles in the Daughter Cell
     – Definition, Mitosis, Meiosis
3. What are the Similarities in Alleles Between Parent Cell and Daughter Cells
     – Outline of Common Features
4. What is the Difference in Alleles Between Parent Cell and Daughter Cells
     – Comparison of Key Differences

Key Terms 

Alleles in the Daughter Cells, Alleles in the Parent Cells, Asexual Reproduction, Mitosis, Meiosis, Sexual Reproduction

What are the Alleles in the Parent Cell 

The alleles in the parent cell are the genetic content of the parent cell. Furthermore, most of the cell types are diploid, and they contain two sets of chromosomes that are homologous. And, each chromosome consists of alleles. The allele pair within the same locus of the homologous chromosomes are alterations of the same gene. And, they can be either homozygous or heterozygous. These alleles are expressed based on their dominant and recessive nature to produce the collection of traits in a particular organism.  

Figure 1: Mitosis

What are the Alleles in the Daughter Cells 

The alleles in the daughter cells are the alleles inherited from the parent cells during reproduction. To produce daughter cells, parent cells can undergo one of the two types of cell divisions: mitosis or meiosis. During asexual reproduction, parent cells undergo mitosis. Here, the genetic content of the parent cells gets doubled by undergoing DNA replication. Then, the parent cell undergoes nuclear division and cytokinesis sequentially to produce two daughter cells. And, the daughter cells produced by mitosis are genetically-identical to the parent cell. Also, both parent cell and its daughter cells contain the same amount of DNA; in other words, the same number of chromosomes. 

Figure 2: Meiosis 

During sexual reproduction, parent cells are responsible for the production of gametes that contains half of the number of chromosomes in the parent cell. That means; each gamete contains one set from the two sets of chromosomes in the parent cell. To do this, the parent cell undergoes meiosis. Here, the DNA of the parent cell undergoes replication. Then, it undergoes meiosis, which consists of two rounds of mitosis-like cell divisions. And, this results in four daughter cells with half of the DNA content of the parent cell. Significantly, during meiosis, chromosomal crossing-over occurs, aiding genetic recombination. Therefore, gametes contain different genetic content or the allele combinations than the parent cell. 

Similarities in Alleles Between Parent Cell and Daughter Cells 

• Alleles in the parent cell and daughter cells contain the genetic information needed by the production of traits in the organism. 
• They are important in the determination of the function of the cell. 

Difference in Alleles Between Parent Cell and Daughter Cells 

Definition 

Alleles in parent cell refer to the genetic content in the parent cell while alleles in daughter cells refer to the genetic content of the daughter cells. 

Genetics 

Alleles in the parent cell are genetically-similar to the alleles in the daughter cells in mitosis while the alleles in the parent cell are genetically-different from the alleles in the daughter cells in meiosis. Thus, this is the main difference in alleles between parent cell and daughter cells.

Amount of Alleles 

The number of alleles in the parent cell is similar to the number of alleles in the daughter cells in mitosis while the number of alleles in the parent cell is twice of that of the daughter cells in meiosis. 

Zygosity 

In parent cells, the alleles occur in pairs and can be either homozygous or heterozygous alleles, while daughter cells contain a single copy of an allele of a particular gene. Hence, this is another difference in alleles between parent cell and daughter cells.

Conclusion 

Alleles in the parent cell are exactly the same in number and genetic content as the alleles in the daughter cells produced by mitosis. However, when a parent cell undergoes meiosis, its number of alleles become half in the producing daughter cells. Therefore, the main difference in alleles between parent cell and daughter cells is their reduction during meiosis. 

Reference:

1. “The Process of Meiosis.” Lumen Learning, Lumen, Available Here

Image Courtesy:

1. “Major events in mitosis” By Mysid – Vectorized in CorelDraw by Mysid from NCBI (Public Domain) via Commons Wikimedia  
2. “Meiosis Overview new” By Rdbickel – Own work (CC BY-SA 4.0) via Commons Wikimedia