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.
Carbon dioxide and water are converted into glucose and oxygen. This produces light energy. Photosynthesis takes place in leaf cells.
Answer:
gap junctions
Explanation:
I don't know how to explain it but that's the answer
please mark brainliest
Answer:
Animals and plants need nitrogen to build amino acids in proteins, which are the building blocks of life. Unlike oxygen, nitrogen cannot be absorbed directly from the air by animals and plants.
Explanation: