A physical environment with different species that interact with one another and with non-living thing is called an ecosystem
        
                    
             
        
        
        
Viruses can multiply very quickly, and so they can go through natural selection at a much quicker rate, allowing certain vaccine resistant mutations to take over a population.
 
        
             
        
        
        
Answer:
- Animals are multicellular.
- Animals are made up of cells that do not have cell walls.
- Most animals reproduce sexually. Some are capable of asexual reproduction by fragmentation, budding, or parthenogenesis.
- Animals are capable of motion in some stage of their lives.
Explanation: