When large pieces of the Earth's outer layer move slowly by plate tectonics, surface features, such as mountains, earthquakes and volcanoes, are formed
Answer:
Answer is 2. Fibroblasts fail to divide.
Explanation:
Tissue culture experiment is the experiment where tissues are grown in an artificial medium. This involves the use of growth medium such as agar or broth. This process help to produce needed tissues in a short period of time.
Fibroblasts are cells which are found in the collective tissues, and they produce collagen. The collagen produced by the Fibroblasts play important role in tissue repair. Fibroblasts are regarded as the main cells in the connective tissue.
Note that, PDGF, which is Platelet -derived growth factor in full, is a growth factor regulating cell growth and it's division.
Metabolic pathways stimulate cell division.
Manufacturers add sugars to their cigarette sometimes in the form of honey, etc. This makes cigarettes more enjoyable, particular and addictive in a way.
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