excretory system: removes waste from blood.
respiratory system: obtains oxygen so the energy in the nutrients can be extracted.
circulatory system: transports nutrients from small intestine to the othet tissues.
nervous system: regulates and controls digestive functioning.
( Am not completly sure, but i think this is the answer)
The cell is hypotonic, when the cell over-expands breaks.
"D: A new gene, which codes for the protein that can repair defective genes, is introduced."
Explanation: <span>Gene therapy is an experimental technique that uses genes to treat or prevent disease. In the future, this technique may allow doctors to treat a disorder by inserting a gene into a patient’s cells instead of using drugs or surgery.</span>
