Answer:
The presence of an additional chromosome
Explanation:
Look at "pair" 21. See how there are THREE chromosomes instead of TWO? Normally, there would only be two chromosomes in each pair but this karyotype shows a trisomy (see def. below) of the 21st pair. This was caused by a nondisjunction mutation of the 21st pair. The is also the karyotype of a person with Down's Syndrome.
Definition of Trisomy:
A condition of the presence of three chromosomes in a pair instead of two. This normally causes developmental irregularity.
I had to take a screenshot of my response since it was getting flagged for being inappropriate for some reason.
Answer:
Electrons are subatomic particles, whose electric charge is negative one elementary charge. They belong to the first generation of the lepton particle family, and are generally thought to be elementary particles because they have no known components or substructure.
Explanation:
230 is your anwser! sorry bad english
