OK so basically the ice age had occurred during the Pleistocene it was about 2.6 billion years ago
        
                    
             
        
        
        
Answer:
The first line of defence (or outside defence system) includes physical and chemical barriers that are always ready and prepared to defend the body from infection. These include your skin, tears, mucus, cilia, stomach acid, urine flow, 'friendly' bacteria and white blood cells called neutrophils.
Explanation:
 
        
             
        
        
        
Water in the ocean move differently depending of the win speed. In the ground, it only moves downward due to gravity pulling in the water while the soil absorbs the water. Water above ground only go one direction due to the slope of the mountain or riven.
        
             
        
        
        
Answer:
Neuron cells
Explanation:
Neurons use axons to carry nerve impulses
 
        
                    
             
        
        
        
Primary consumers<span> only obtain a fraction of the total solar energy—about 10%—captured by the producers they eat. The other 90% is used by the producer for growth, reproduction, and survival, or it is lost as </span>heat<span>. You can probably see where this is going. Primary consumers are eaten by </span>secondary consumers<span>. An example would be birds that eat bugs that eat leaves. </span>Secondary consumers<span> are eaten by </span>tertiary consumers<span>. Cats that eat birds that eat bugs that eat leaves, for instance.</span>