Search results
Results from the WOW.Com Content Network
In humans with non-injured tissues, the tissue naturally regenerates over time; by default, new available cells replace expended cells. For example, the body regenerates a full bone within ten years, while non-injured skin tissue is regenerated within two weeks. [2] With injured tissue, the body usually has a different response.
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.
Compensatory growth is a type of regenerative growth that can take place in a number of human organs after the organs are either damaged, removed, or cease to function. [1] Additionally, increased functional demand can also stimulate this growth in tissues and organs. [2]
Cataplexy is considered secondary when it is due to specific lesions in the brain that cause a depletion of the hypocretin neurotransmitter. Secondary cataplexy is associated with specific lesions located primarily in the lateral and posterior hypothalamus. Cataplexy due to brainstem lesions is uncommon particularly when seen in isolation. The ...
When a nerve axon is severed, the end still attached to the cell body is labeled the proximal segment, while the other end is called the distal segment. After injury, the proximal end swells and experiences some retrograde degeneration, but once the debris is cleared, it begins to sprout axons and the presence of growth cones can be detected.
In early development different vertebrate species all use essentially the same inductive signals and the same genes encoding regional identity. Even invertebrates use a similar repertoire of signals and genes although the body parts formed are significantly different.
The four types of regeneration are epimorphosis, stem cell mediated regeneration, morphallaxis, and compensatory regeneration (compensatory hyperplasia). Epimorphosis occurs when other adult cells in a damaged tissue undergo dedifferentiation and then divide to form an undifferentiated mass of tissue, this new mass encompasses the mass of ...
The headless fragment must regenerate a completely new head. In 'paratomy', the split occurs perpendicular to the antero-posterior axis and the split is preceded by the "pregeneration" of the anterior structures in the posterior portion. The two organisms have their body axis aligned i.e. they develop in a head to tail fashion.