The correct answer is (c) synapsis and crossing over. During prophase I of meiosis, synapsis and crossing over take place.
Which event occurs during prophase answers?
Prophase represents the first stage of actual cell division (in both mitotic and meiotic cell division). It involves breakdown of nuclear envelope, nucleolus starts to disappear, and condensation of chromatin into chromosomes takes place.
What process occurs in prophase I?
Explanation: During prophase I, homologous chromosomes pair with each other and exchange genetic material in a process called chromosomal crossover. The exchange occurs in segments over a small region of homology (similarity in sequence, ie., the same alleles).
What is meant by prophase?
Prophase is the first phase of mitosis, the process that separates the duplicated genetic material carried in the nucleus of a parent cell into two identical daughter cells. During prophase, the complex of DNA and proteins contained in the nucleus, known as chromatin, condenses.
What are the key features of prophase?
- chromosomes condense and become visible.
- spindle fibers emerge from the centrosomes.
- nuclear envelope breaks down.
- nucleolus disappears.
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.
What do prophase cells look like?
When you look at a cell in prophase under the microscope, you will see thick strands of DNA loose in the cell. If you are viewing early prophase, you might still see the intact nucleolus, which appears like a round, dark blob.
What are the two parts of cell division?
There are two types of cell division: mitosis and meiosis. Most of the time when people refer to “cell division,” they mean mitosis, the process of making new body cells.
What are the 5 stages of prophase 1?
Meiotic prophase I is subdivided into five stages: leptotene, zygotene, pachytene, diplotene, and diakinesis.
What occurs during Diplotene?
In the diplotene stage the synaptonemal complexes loosen and partial separation of each pair of sister chromatids from their homologous counterparts occurs. The chromatids are still held together at the centromeres and the sites of crossing over. The dictyotene stage is the resting phase of the oocyte.