Hello!
Ions are charged particles, that explains why they have either a positive or negative charge. Since electrical signals contain charges, that also explains why they are often based on ions. Your answer would be D!
You can feel free to let me know if you have any questions regarding this!
Thanks!
- TetraFish
        
                    
             
        
        
        
Answer:
Stem cells are cells in the human body that have the ability to develop into many other body cell types. Stem cells are very useful for drug development, research, they aren't likely to be rejected in transplants, and are used to repair damaged or diseased cells and tissues. However, they cannot be grown for long periods of time, there are very small numbers in each tissue and cell making them very hard to find, and for certain studies they have been shown to cause cancer. To be honest, using them in research does have its pros and cons, they are very useful and easier to use in research, plus they can help repair damaged and diseased cell tissues. But at the same time they can be difficult to use correctly and properly, it can cause serious health problems if cancer doesn't take place. I think that using them in research is okay, as long as they are used correctly and properly.
Hope this helps! :)
 
        
             
        
        
        
Answer:
D Copper is transported by the stem from the roots to the flowers, where it affects reproductive tissues.
Explanation: