Chromatin is too thin to be seen using a light microscope. As a cell prepares to divide, its chromatin coils up, forming tight, distinct chromosomes that are visible under a light microscope.
How do chromosomes become visible under a light microscope as a cell prepares to divide?
These fibers consist of chromatin, a combination of DNA and protein molecules. As a cell prepares to divide, its chromatin fibers condense, becoming visible as the compact structures called chromosomes.
Which structures form the spindle fibers during cell division and guide the duplicated chromosomes to their daughter cells quizlet?
Centrioles (help to form the spindle fibers) 2. Spindle fibers (separate the chromosomes) –> in mitosis the spindle fibers pull apart sister chromatids–in anaphase 1 of meiosis the spindle fibers separate tetrads (2 sets of homologous chromosomes)– in anaphase 2 spindle fibers pull apart sister chromosomes.
What form does the chromosome take when the cell is not dividing quizlet?
The complex of DNA and proteins that makes up a eukaryotic chromosome. When the cell is not dividing, chromatin exists as a mass of very long, thin fibers that are not visible with a light microscope. You just studied 63 terms!
Is chromosomes visible under light microscope?
Chromosomes are not visible in the cell’s nucleus—not even under a microscope—when the cell is not dividing. However, the DNA that makes up chromosomes becomes more tightly packed during cell division and is then visible under a microscope. … DNA and histone proteins are packaged into structures called chromosomes.
What three phases are individual chromosomes no longer visible?
It is during interphase, telophase, and cytokinesis that the chromosomes are no longer visible.
What does this mean in terms of how the cell grows and divides?
A cell cycle is a series of events that takes place in a cell as it grows and divides. A cell spends most of its time in what is called interphase, and during this time it grows, replicates its chromosomes, and prepares for cell division. The cell then leaves interphase, undergoes mitosis, and completes its division.
What happens to a chromosome during cell division quizlet?
Metaphase: chromosomes line up across middle of the cell with spindle fibers connected to their centromeres. Anaphase: sister chromatids separate and move apart. Telophase: chromosomes gather at opposite ends of the cell and lose distinct shape; new nuclear membranes form.
What form is DNA in when a cell is not dividing?
DNA is present in both dividing & non-dividing cells. In non- dividing cells, the chromatin threads contain DNA which later condense to form chromosomes during dividing phase. DNA is the genetic material present in all cells.