The main events of prophase are: the condensation of chromosomes, the movement of the centrosomes, the formation of the mitotic spindle, and the beginning of nucleoli break down.
What are 2 things that first appear during prophase?
- chromosomes condense and become visible.
- spindle fibers emerge from the centrosomes.
- nuclear envelope breaks down.
- nucleolus disappears.
What happens during prophase stage?
During prophase, the complex of DNA and proteins contained in the nucleus, known as chromatin, condenses. The chromatin coils and becomes increasingly compact, resulting in the formation of visible chromosomes. Chromosomes are made of a single piece of DNA that is highly organized.
What are the 5 stages of prophase 1?
Meiotic prophase I is subdivided into five stages: leptotene, zygotene, pachytene, diplotene, and diakinesis.
What is the function of prophase 1?
Prophase I highlights the exchange of DNA between homologous chromosomes via a process called homologous recombination and the crossover at chiasma(ta) between non-sister chromatids. Thus, this stage is important to increase genetic variation.
Why is crossing over important?
This process, also known as crossing over, creates gametes that contain new combinations of genes, which helps maximize the genetic diversity of any offspring that result from the eventual union of two gametes during sexual reproduction.
What is a prophase 1?
1 : the initial stage of mitosis and of the mitotic division of meiosis characterized by the condensation of chromosomes consisting of two chromatids, disappearance of the nucleolus and nuclear membrane, and formation of mitotic spindle.