Answer
The maximum number of DNA molecules ever contained in a cell over the course of its life cycle depends on the type of cell and the species in question. Let's consider a diploid somatic cell in a human as an example.
1. **Diploid Somatic Cell:** In humans, most of our somatic (body) cells are diploid, meaning they have two sets of chromosomes, one from each parent. Humans typically have 46 chromosomes, or 23 pairs. Therefore, a diploid somatic cell has 46 DNA molecules (two copies of each chromosome).
2. **Cell Replication:** Throughout the cell's life cycle, it goes through a series of divisions, including mitosis for growth and tissue repair. During mitosis, the DNA is replicated, but the total number of DNA molecules remains the same because each replicated DNA molecule pairs with its original, resulting in two identical copies.
3. **Cell Division:** When a diploid somatic cell divides by mitosis, it gives rise to two daughter cells, each with the same number of DNA molecules as the parent cell (i.e., 46 DNA molecules).
4. **Maximum Number of DNA Molecules:** The maximum number of DNA molecules in a diploid somatic cell occurs at the beginning of its life cycle when it is first formed. At this stage, it has 46 DNA molecules.
Throughout its life cycle, as the cell divides and replicates, the number of DNA molecules remains relatively constant at 46, with the exception of certain specialized cells, like germ cells (sperm and egg cells), which undergo meiosis to reduce their DNA content by half.
It's important to note that the number of DNA molecules can vary in different types of cells (e.g., haploid cells like gametes have half the number of DNA molecules as diploid cells), and this answer is specific to diploid somatic cells in humans. Different organisms and cell types may have different DNA molecule numbers and life cycle strategies.
Work Step by Step
The maximum number of DNA molecules ever contained in a cell over the course of its life cycle depends on the type of cell and the species in question. Let's consider a diploid somatic cell in a human as an example.
1. **Diploid Somatic Cell:** In humans, most of our somatic (body) cells are diploid, meaning they have two sets of chromosomes, one from each parent. Humans typically have 46 chromosomes, or 23 pairs. Therefore, a diploid somatic cell has 46 DNA molecules (two copies of each chromosome).
2. **Cell Replication:** Throughout the cell's life cycle, it goes through a series of divisions, including mitosis for growth and tissue repair. During mitosis, the DNA is replicated, but the total number of DNA molecules remains the same because each replicated DNA molecule pairs with its original, resulting in two identical copies.
3. **Cell Division:** When a diploid somatic cell divides by mitosis, it gives rise to two daughter cells, each with the same number of DNA molecules as the parent cell (i.e., 46 DNA molecules).
4. **Maximum Number of DNA Molecules:** The maximum number of DNA molecules in a diploid somatic cell occurs at the beginning of its life cycle when it is first formed. At this stage, it has 46 DNA molecules.
Throughout its life cycle, as the cell divides and replicates, the number of DNA molecules remains relatively constant at 46, with the exception of certain specialized cells, like germ cells (sperm and egg cells), which undergo meiosis to reduce their DNA content by half.
It's important to note that the number of DNA molecules can vary in different types of cells (e.g., haploid cells like gametes have half the number of DNA molecules as diploid cells), and this answer is specific to diploid somatic cells in humans. Different organisms and cell types may have different DNA molecule numbers and life cycle strategies.
