Answer= Because polar bears depend on ice as a habitat to survive the more the temperature is rising and the sea ice melting as a result of global warming there is basically a possibility that the population of polar bears will decline because there will be no home (habitat)left for them to breed(survive)in.
        
                    
             
        
        
        
A, because, the entire point of his theory was to prove that changes don't happen spotaneously!
 
        
                    
             
        
        
        
Answer:
Most invertebrates (and higher animals) can be placed in one of two groups based on how they develop as embryos. The two groups are called protostomes and deuterostomes. ... It shows that echinoderms are more closely related to chordates than are the other invertebrate phyla. Explanation:
 
        
                    
             
        
        
        
Answer:
d. Ribosome
f. Cell wall
Explanation:
In humans 80s type of ribosome is present and in bacteria 70s type of ribosome is present. Human cells do not have cell wall while bacterial cells have peptidoglycan cell wall. These differences can be targeted by the potential antibacterial agents. 
For example, tetracycline antibiotic inhibits the binding of important molecules to bacterial ribosome which ultimately inhibits the protein synthesis in bacteria. Vancomycin antibiotic on other hand inhibits the cell wall formation in bacteria by inhibiting peptidoglycan synthesis.