What significant event occurs during Prophase 1 of meiosis?

What significant event occurs during Prophase 1 of meiosis?

• A. Chromosomes coil up and spindle forms
• B. Homologous chromosomes separate
• C. Nondisjunction occurs
• D. Cells undergo mitosis

Answer: (A)

During Prophase 1 of meiosis, a significant event is the coiling up of chromosomes and the formation of the spindle apparatus. This stage is characterized by the condensation of chromatin into visible chromosomes, which allows them to become distinguishable under a microscope. Each chromosome pairs with its homologous chromosome, forming structures known as tetrads, where genetic recombination (crossing over) may occur. The spindle apparatus begins to form during this phase, preparing the cell for the subsequent stages of meiosis. This is essential for the proper segregation of chromosomes during the later stages of meiosis. The coiling of chromosomes and spindle formation are critical for ensuring that the genetic material is accurately divided into the resulting gametes. The other options refer to events that either occur in different stages of meiosis or are not characteristic of Prophase 1. The pairing of homologous chromosomes and genetic recombination are specifically relevant to this phase, highlighting its importance in meiosis and genetic diversity.

During Prophase 1 of meiosis, a significant event is the coiling up of chromosomes and the formation of the spindle apparatus. This stage is characterized by the condensation of chromatin into visible chromosomes, which allows them to become distinguishable under a microscope. Each chromosome pairs with its homologous chromosome, forming structures known as tetrads, where genetic recombination (crossing over) may occur.

The spindle apparatus begins to form during this phase, preparing the cell for the subsequent stages of meiosis. This is essential for the proper segregation of chromosomes during the later stages of meiosis. The coiling of chromosomes and spindle formation are critical for ensuring that the genetic material is accurately divided into the resulting gametes.

The other options refer to events that either occur in different stages of meiosis or are not characteristic of Prophase 1. The pairing of homologous chromosomes and genetic recombination are specifically relevant to this phase, highlighting its importance in meiosis and genetic diversity.