Why are spindle fibers important during mitosis?
A. They help separate the
B. chromosomes.
C. They break down the nuclear membrane.
D. They duplicate the DNA
E. They divide the cell in half.
A. They help separate the chromosomes.
The correct answer is A. They help separate the chromosomes.
During mitosis, spindle fibers are critical for the proper distribution of chromosomes to the daughter cells. They are responsible for connecting to the chromosomes and providing the force necessary to move them to opposite ends, or poles, of the dividing cell. This ensures that each daughter cell receives the correct number and type of chromosomes.
To understand why spindle fibers are important, we need to understand mitosis. Mitosis is the process of cell division that ensures new cells receive an identical copy of the genetic material (DNA) as the parent cell. This DNA is organized into structures called chromosomes. Before a cell can divide, the chromosomes must be accurately separated and evenly distributed to the daughter cells.
The spindle fibers are formed by microtubules, which are long, hollow tubes. They originate from two structures called centrosomes, located at opposite ends of the cell. The spindle fibers extend between the centrosomes and attach themselves to specialized regions of the chromosomes called the kinetochores. The kinetochores are protein complexes located on the centromere of each chromosome.
Once all the chromosomes are appropriately attached to the spindle fibers, the fibers begin to contract and pull the chromosomes towards the opposite poles of the dividing cell. This process ensures that each daughter cell receives an equal and complete set of chromosomes. Once the chromosomes are properly separated, the cell can proceed with the final stages of division.
It is important to note that while spindle fibers play a crucial role in chromosome separation, other cellular components also contribute to the process of mitosis. These include the cell's cytoskeleton, the nuclear membrane, and additional proteins and enzymes. However, the specific function of spindle fibers is to provide the mechanical force necessary for accurate chromosome movement during mitosis.
The correct answer is:
A. They help separate the chromosomes.
During mitosis, spindle fibers play a crucial role in separating the duplicated chromosomes in the cell. These fibers attach to the chromosomes and help move them to opposite ends of the cell. This ensures that each resulting daughter cell receives the correct number of chromosomes.