The twisted shape of DNA is called Double Helix
Answer:
C. the ability to replace all S alleles in human red blood cells
Explanation:
When Sarah performed this experiment, she changed the levels of nitrogen in order to observe the changes in the morphological features of the plant.
All of the characteristics of the plant that she observed were dependent on multiple different things, but the level of nitrogen was an independent variable that she was changing at her will.
you have to count the lines so the answer is 15