Search results
Results from the WOW.Com Content Network
Regeneration is different from reproduction. For example, hydra perform regeneration but reproduce by the method of budding. The regenerative process occurs in two multi-step phases: the preparation phase and the redevelopment phase. [10] [11] Regeneration begins with an amputation which triggers the first phase.
The consequence of this asexual method of reproduction is that all the cells are genetically identical, meaning that they have the same genetic material (barring random mutations). Unlike the processes of mitosis and meiosis used by eukaryotic cells, binary fission takes place without the formation of a spindle apparatus on the cell.
The terminal cell elongates more than the deeper cells; then the production of a lateral bisector takes place in the inner fluid, which tends to divide the cell into two parts, of which the deeper one remains stationary, while the terminal part elongates again, forms a new inner partition, and so on.
The cells that contain the determinant become a signaling center and emit an inducing factor. Because the inducing factor is produced in one place, diffuses away, and decays, it forms a concentration gradient, high near the source cells and low further away.
Fertilization takes place when the spermatozoon has successfully entered the ovum and the two sets of genetic material carried by the gametes fuse together, resulting in the zygote (a single diploid cell). This usually takes place in the ampulla of one of the fallopian tubes. The zygote contains the combined genetic material carried by both the ...
The study, published in the journal Cell by Cell Press, concluded that extended fasting activates the adrenal glands, which then stops tissue regeneration during "periods of unstable nutrient supply."
An asymmetric cell division produces two daughter cells with different cellular fates. This is in contrast to symmetric cell divisions which give rise to daughter cells of equivalent fates. Notably, stem cells divide asymmetrically to give rise to two distinct daughter cells: one copy of the original stem cell as well as a second daughter ...
France's government collapsed Wednesday after Prime Minister Michel Barnier was forced out in a no-confidence vote in Parliament, reigniting a summertime political crisis for the country as it ...