1. All known living things are made up of one or more cells.
2. All living cells arise from pre-existing cells by division. 
3. The cell is the fundamental unit of structure and function in all living organisms.
I hope that this helps you !
        
                    
             
        
        
        
Answer:
A)  A decrease in Na+ permeability, and an increase in K+ permeability.
Explanation:
When the potential action reaches a peak of about +40 mv Na+ channels are open and a high number of Na+ ions are entering the inside of the cell. Shortly after this happens the K+ channels will start to open their gates increasing the cell  K+ permeability  while the Na+ channels will start to close their gates, so the Na+ permeability will decrease. This happens  in order to valance the positive charge on the inside of the cell. Normally the inside has a negative charge while the outside has a positive one, as the inside is more positive due to the increase in Na+ permeability at the beginning of the potential action, K+ cations (which are in abundance in the cell) will have to go out through the K+ channels  so as to restore the charge valance, that means that there is an increase in K+ permeability. 
 
        
             
        
        
        
Scientists often perform experiments to check and recheck their work.  They also redo these experiments to ensure correct results.
 
        
             
        
        
        
From the above foods; oil, bread, steak, chicken, butter and pretzel, only 2 contain lots of carbohydrates. Colour the bread and the pretzel.
 
        
                    
             
        
        
        
The answer is electron microscope, the magnification can be so high that it can be very expensive, most schools doesnt have them, mostly found in universities or some laboratories. the ones we usually use in home or schools are light microscope