What Is Meiotic Interphase?

Cells spend most of their lifetimes in interphase.
••• Duncan Smith/Photodisc/Getty Images

To grow, repair and reproduce, cells undergo one of two cell division processes: mitosis or meiosis.

Mitosis produces two daughter cells that have the same number of chromosomes as the mother cell. With meiosis, four daughter cells with half the number of chromosomes as the mother cell are produced. Although the process of mitosis and meiosis differs, what occurs during the interphase stage of meiosis is the same as that of mitosis.

In this post, we're going over what the meiosis definition is, what meiosis interphase is specifically and where it is during the steps of meiosis.

Meiosis Definition

The general meiosis definition is cell division that results in four haploid cells (half the "normal" amount of DNA) from one mother cell. It's used for the creation of gametes like eggs, sperm and spores in some types of plants.

The general steps of meiosis are: interphase (separated into G1, S, and G2 phases), prophase 1, metaphase 1, anaphase 1, telophase 1, prophase 2, metaphase 2, anaphase 2 and telophase 2.

In this post, we're going to focus on meiosis interphase.

G1 Phase: Doing Their Job

During the first phase of meiosis interphase -- known as G1 -- cells grow and perform many of their required cellular functions. These functions can include producing proteins and transmitting signals to or receiving signals from other cells.

During this phase, the chromosomes are housed within a nuclear membrane.

S Phase: Doubling Time

Interphase is a time for the cell to prepare for meiosis and part of this preparation involves doubling the number of chromosomes the cell contains. This part of interphase is known as S phase, with the S standing for synthesis. Each chromosome ends up with an identical twin called sister chromatids.

The twins are joined together in a dense area called a centromere. These joined twin chromosomes are called sister chromatids. During the S phase, the nuclear envelope is still in place and the chromatids are not distinct. In the cells of plants, a spindle that will eventually pull the chromatids apart develops during the S phase.

G2 Phase: Preparing for Action

Most of the final phase of meiotic interphase is much like the G1 phase and is known simply as the G2 phase. The cell continues to grow and perform its cellular duties with the double chromosomes tucked inside a nuclear membrane. At the final moments of the G2 phase in animal cells, bundles of microtubules called centriole pairs duplicate within the centrosome and become well-defined.

These two centriole pairs will later produce the spindle of fibers that will pull the sister chromatids apart. During the other phases of interphase, the centrosome has only one centriole pair and appears as a poorly defined dark spot near the nucleus.

Completing the First and Second Division

Unlike mitosis where only one division occurs, cells undergoing meiosis experience two cell divisions. The first division is similar to mitosis and results in two daughter cells with the same number of chromosomes as the mother cell. These two daughter cells then experience a second division to make four cells.

Because there is no second interphase between the two divisions of meiosis, the chromosomes within the two daughter cells do not have time to double again before this second split. The second division halves the chromosome number in the two daughter cells, producing four cells with only half the number of chromosomes as the original mother cell.

Thus, when two gametes join together, they form a fertilized zygote that has a diploid number of chromosomes and begins developing into a new organism.

Related Articles

What Are the Special Things That Happen When Cells...
Which Event Will Follow DNA Replication in a Cell Cycle?
When Do Chromosomes Duplicate During a Cell Life Cycle?
The Difference Between Anaphase, Interphase, Metaphase...
List the Steps of the Cell Cycle in Order
How Does Cytokinesis Differ in Plants & Animals?
Why Does DNA Content Increase During Interphase?
Telophase: What Happens in this Stage of Mitosis &...
What Types of Cells & Organisms Undergo Mitosis & Meiosis?
Does Mitosis Occur in Prokaryotes, Eukaryotes, or Both?
What Happens to a Cell If It Does Not Copy DNA Chromosomes...
Difference Between Plant & Animal Cell Division
What Forms Across the Center of a Cell Near the End...
Stage in Which the Nucleus & Nucleolus Are Reformed
Reproductive System of a Pigeon
The Difference Between Seeds and Spores
Meiosis: Definition, Phases 1 & 2, Difference from...
Similarities of Mitosis and Meiosis
Two Purposes of Mitosis