Answer & Explanation:
Plant cells are still able to divide without centrioles because the spindle fibers form outside the nuclear envelope.
Hope that helps! :]
Some chemicals increase the mutation rate, physical agents such as radiation also increase the mutation rate. There are viruses that are mutagens as well. Also, the number of mutations that an organism produce can also be phenotypically plastic.
Hope this helps. (This is the definition my bio teacher gave me.)
Answer:
Deletion mutation refers to the deletion of a sequence of DNA or a part of a chromosome.
It can vary from a deletion of a single nucleotide to an entire chromosome.
It is usually caused by errors during replication, errors during crossing over, and translocation.
Deletion can cause various genetic disorders in human, for example, Williams syndrome (deletion of genetic material from chromosome 7), cystic fibrosis (2/3rd cases are caused by deletion of three nucleotides from chromosome 7), cri du chat syndrome (due to deletion mutation occur in chromosome 5) et cetera.
It can also lead to infertility in males.
In extreme cases, it can also lead to the death of an individual.