Centromeres are proteins that attach sister chromatids together. They are usually located in the center, or middle of the chromatids. The two sister chromatids together create a chromosome. The chromatids stay together with the centromeres until anaphase, when they separate into the two new daughter cells.
Centrosomes are often associated with the nuclear membrane during interphase of the cell cycle. In mitosis the nuclear membrane breaks down and the centrosome nucleated microtubules can interact with the chromosomes to build the mitotic spindle.
The mother centriole, the one that was inherited from the mother cell, also has a central role in making cilia and flagella.
The centrosome is copied only once per cell cycle so that each daughter cell inherits one centrosome, containing two centrioles. The centrosome replicates during the S phase of the cell cycle. During the prophase in the process of cell division called mitosis, the centrosomes migrate to opposite poles of the cell. The mitotic spindle then forms between the two centrosomes. Upon division, each daughter cell receives one centrosome. Aberrant numbers of centrosomes in a cell have been associated with cancer. Doubling of a centrosome is similar to DNA replication in two respects: the semiconservative nature of the process and the action of cdk2 as a regulator of the process.[9] But the processes are essentially different in that centrosome doubling does not occur by template reading and assembly. The mother centriole just aids in the accumulation of materials required for the assembly of the daughter centriole.[10]
Centrosome (shown by arrow) next to nucleus
In animal cells, centrosomes contain two structures called centrioles. Interestingly, centrioles are not required for the progression of mitosis. When the centrioles are irradiated by a laser, mitosis proceeds normally with a morphologically normal spindle. Moreover, development of the fruit fly Drosophilais largely normal when centrioles are absent due to a mutation in a gene required for their duplication.[11] In the absence of the centrioles the microtubules of the spindle are focused by motors allowing the formation of a bipolar spindle. Many cells can completely undergo interphase without centrioles.[8] Unlike centrioles, centrosomes are required for survival of the organism. Acentrosomal cells lack radial arrays of astral microtubules. They are also defective in spindle positioning and in ability to establish a central localization site in cytokinesis. The function of centrosome in this context is hypothesized to ensure the fidelity of cell division because it greatly increases the efficacy. Some cell types arrest in the following cell cycle when centrosomes are absent. This is not a universal phenomenon.
When the nematode C. elegans egg is fertilized the sperm delivers a pair of centrioles. These centrioles will form the centrosomes which will direct the first cell division of the zygote and this will determine its polarity. It is not yet clear whether the role of the centrosome in polarity determination is microtubule dependent or independent.
Centrioles are protein based structures in animal cells that form spindle fibres which pull the chromosomes apart in mitosis to divide the cell.
the role is to join the two sister chromatids together
centrosome help in attaching spindle fibers which led to separation of chromosomes and and also help in chromosomal movements
Centrioles are a part of the centrosome, which is responsible for manufacturing microtubles which help cells divide during mitosis
During anaphase centromeres complete duplication.
They organize the microtubules
Centrosomes replicate during the S phase of the CELL CYCLE not mitosis. Mitosis is one stage of the cell cycle. Replication does not happen during mitosis(M phase). It happens during the S phase. In fact, the opposite happens chromosomes are consdensed and packaged in preparation for splitting.
During mitosis, the chromosomes are pulled away by spindle fibers that come from each pair of centrioles at the opposite ends of the cell. The reason this happens is so that each new daughter cell gets the same chromosomes as the parent cell had.
prophase source:mb
Yes, because in order for things to grow, (humans), cells have to divide to make new ones
Actually, while centrosomes play a big part in interphase of mitosis, they are not needed for cell reproduction. Studies have shown that the spindle-fibers still form via motors at the poles of the cell.
centrosomes
During mitosis, the centrosomes move apart and create the spindle fibers. The centrosomes, which contain two centrioles, migrate to opposite poles of the cell. These centrosomes then form the spindle fibers, which attach to the chromosomes and aid in their separation during cell division.
Centrosomes replicate during the S phase of the CELL CYCLE not mitosis. Mitosis is one stage of the cell cycle. Replication does not happen during mitosis(M phase). It happens during the S phase. In fact, the opposite happens chromosomes are consdensed and packaged in preparation for splitting.
During mitosis, the chromosomes are pulled away by spindle fibers that come from each pair of centrioles at the opposite ends of the cell. The reason this happens is so that each new daughter cell gets the same chromosomes as the parent cell had.
prophase source:mb
Yes, because in order for things to grow, (humans), cells have to divide to make new ones
Actually, while centrosomes play a big part in interphase of mitosis, they are not needed for cell reproduction. Studies have shown that the spindle-fibers still form via motors at the poles of the cell.
During the anaphase stage of mitosis the two chromatids become separate chromosomes. The chromatids are pulled apart and move toward their centrosomes. As they move toward the poles, the centrosomes go first, followed by the chromatids, forming a â??vâ?? shape.
Prophase.
During the process of mitosis, the nucleus divides!
The equatorial plate happens in mitosis during cytokineses.
the ikterpuschles the microtubules organize spindle fibres during mitosis and meiosis