I think that having an extra chromosome 21 is tolerable to the point that someone with this condition can survive to maturity because it does not replicate.
There should only be a pair of chromosome 21. In the event that there are 3 chromosome 21, the person that has this extra chromosome has Down syndrome. Changes in the number and structure of this chromosome may result to delayed development, intellectual disability, but not immediate death.
Answer:
The answer is D. Double Helix
Explanation:
Red and yellow bell........... - genetic diversity
A park has....... - species diversity
Five different bird..... - species diversity.
The cell membrane functions as a selective barrier. We call these kind of membranes as differentially permeable or semi permeable membrane. It can decide what substances can pass in and out. Therefore it can surround the cytoplasm (which is the inside of a cell) to separate the cell's content from the surroundings.
The number of neutrons in each atom