Table of Contents
During which phase does the DNA begin to appear grainy and start to condense?
Mitosis begins. Transcription stops, and the DNA begins to appear grainy as it starts to condense. The nuclear envelope begins to break up and the centrosome gets duplicated. The duplicated chromosomes become visible as they condense.
During what stage does the G1 S and G2 phases happen?
Interphase
Interphase is composed of G1 phase (cell growth), followed by S phase (DNA synthesis), followed by G2 phase (cell growth). At the end of interphase comes the mitotic phase, which is made up of mitosis and cytokinesis and leads to the formation of two daughter cells.
During what phase does the chromatin in the nucleus of a cell condense and become visible?
During interphase, the cell’s DNA is not condensed and is loosely distributed. A stain for heterochromatin (which indicates the position of chromosomes) shows this broad distribution of chromatin in a mouse cell (upper left). The same stain also shows the organized, aligned structure of the chromosomes during mitosis.
What is the phase where chromatin condenses to form chromosomes?
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.
What happens to the nucleus during the mitotic phase?
During the multistep mitotic phase, the cell nucleus divides, and the cell components split into two identical daughter cells. During prophase, the nucleus disappears, spindle fibers form, and DNA condenses into chromosomes ( sister chromatids ).
When do chromosomes become visible in the nucleus?
In what stage do the chromosomes become visible? During interphase (1), chromatin is in its least condensed state and appears loosely distributed throughout the nucleus. Chromatin condensation begins during prophase (2) and chromosomes become visible. Chromosomes remain condensed throughout the various stages of mitosis (2-5).
Why is interphase called the first gap in the cell cycle?
In order for a cell to move from interphase into the mitotic phase, many internal and external conditions must be met. The three stages of interphase are called G 1, S, and G 2. The first stage of interphase is called the G 1 phase (first gap) because, from a microscopic aspect, little change is visible.
How are chromosomes aligned during the metaphase phase?
During metaphase, the “change phase,” all the chromosomes are aligned on a plane called the metaphase plate, or the equatorial plane, midway between the two poles of the cell. The sister chromatids are still tightly attached to each other by cohesin proteins.