When do chromosomes become visible during mitosis?
Chromosomes condense becoming visible during the prophase part of mitosis which is the stage between interphase and metaphase.
It is possible to count chromosomes only during vell division (mitosis or meiosis). This is because when the cell is not dividing the chromosomes are in an uncoiled, extended state and are not visible under the microscope. During cell division the chromosomes coil up, becoming shorter and thicker and so visible. At this time they can be counted.
The phase of mitosis in which the chromosomes become invisible is during interphase. This is because the chromatin is unwound and therefore barely visible so the cell seems inactive. However, interphase is actually a very active time. Source: Third Edition- Biology Concepts and Investigations. Marielle Hoefnagels. Page 154
The four stages of mitosis are, prophase metaphase, and anaphase, and telophase. Prophase is the longest and first phase during mitosis, it takes about 50 to 60 percent of the time. During the phase the chromosomes become visible. The centrioles are two tiny structures located in the cytoplasm. Metaphase is the second phase of mitosis that only lasts a few minutes. During this phase the chromosomes line up across the center of the cell. Anaphase…