What did you include in your response? Medications can be tested on cell cultures instead of being injected into patients unnecessarily. Cancer cells continue to grow in the cultures uncontrollably allowing scientists to test multiple medications on the cancer cells. Specific treatments that are shown to fight the growth of cancer cells in the culture can be used on patients. Cultures are safer to use than injections of unneeded medications into patients.

The statements are correct.

Explanation:  

Cell culture is a technique widely used in molecular biology where cell lines are grown in controlled conditions, thus allowing to make experiments and to test compounds that may result useful to treat diverse diseases, including cancer.  

Immortalized cell lines are characterized for their ability to proliferate indefinitely which are derived from oncogenic tissues. In cancer research, these lines are used as models to test different drugs and to study cellular mechanisms associated with cancer progression including, among others, proliferation, invasiveness, vascularization, etc. In addition, the mechanisms associated with the death of cancer cells such as, for instance, apoptosis, may also be studied by using immortalized lines.

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.