A teacher writing to a confused student. 
bacteria are microscopic (very tiny) organisms that are unicellular (made up of a single cell). One fundamental difference is that bacterial cells lack intracellular organelles, such as mitochondria, chloroplasts, and a nucleus, which are present in both animal cells and plant cells.
 
        
             
        
        
        
Answer: Possible consequences of climate change to species that have a narrow temperature tolerance range are extinction, change in migratory patterns, and decreased population.
        
             
        
        
        
Synathropic  is  the  term  which  is  used  to   describe  fly  species  which  exploit  foods and habitat  created  by  agriculture  and other  human  activities. They   are  considered as pest   and  also as  vectors  to  diseases which   live  near  human and  benefit from   human and their  dwelling.
        
                    
             
        
        
        
Answer:
Invertebrates can have bilateral or radial symmetry, or they can be asymmetrical. Bilateral symmetry means that the animal is arranged in the same way on both sides. Radial symmetry means the body parts are arranged in a circle around a central point.