<span>1) a five carbon ribose sugar, 2) a phosphate molecule and 3) one of four nitrogenous bases: adenine, guanine, cytosine or uracil.</span>
        
             
        
        
        
Why do most cells in the human body divide infrequently? They have exited the cell cycle and entered G0. The free-energy change for the oxidation of glucose to CO2 and water is -686 kcal/mol, and the free-energy change for the reduction of NAD+ to NADH is +53 kcal/mol
        
             
        
        
        
Answer: hypotonic, isotonic, hypertonic
Explanation: The tonicity of a solution depends in part on its concentration of the solute that can not pass the membrane (non penetrating solute) relative to that inside the cell.
Hypotonic solution (hypo means less): contains less concentration of non penetrating solute relative to that inside the cell. Water will enter the cell and the cell will swell and late. 
Isotonic solution (Iso means same): it contains thesame solute relative to that in the cell, there will be no net movement of water across the plasma membrane.
Hypertonic solution (hyper means more) Hypertonic solution contain more solute relative to that in the cell. Hence the cell will lose water to its environment and may shrink and die.
 
        
             
        
        
        
Answer:
When you get sick first time your body will produce antibodies and destroy that bacteria or virus after producing that antibody your body has memory cell specialised for that antibody so you won't get sick everytime when you get that specific type of antigen