Answer:
A shark's skeleton is made of cartilage , a type of strong but flexible tissue .Most other fish are covered in smooth , flat scales . A shark is covered in sharp , toothlike scales called denticles . Most other fish have flaps over their gills.
Explanation:
I hope it's help yu and plz mark me brainliest........... plz plz plz
 
        
                    
             
        
        
        
I believe he is looking for an allele
An allele is a variant form of a gene. Some genes have a variety of different forms, which are located at the same position, or genetic locus, on a chromosomes. Humans are called diploid organisms because they have two alleles at each genetic locus, with one allele inherited from each parent.
        
             
        
        
        
I think this information may be help you
The plants in a specific environment be impacted if there was a sudden drop in the amount of bacteria present in that area, there are positive and negative consequences associated with this situation.
Positive:
The decrease in bacterial colonization will prevent the plant from the diseases caused by the bacteria and this will promote plant growth. Like, black rot in Brassica caused by Xanthomonas campestris, bacterial canker in tomato, capsicum and chilli caused by Clavibacter michiganesis. 
Negative:
Plants remains in symbiotic relationship with bacteria in order to obtain impermeable inorganic minerals from the soil. In the absence of bacteria, the plants will not receive these nutrients, and their growth may be hampered. Example bacteria fixes atmospheric nitrogen which is taken up by the root nodules of leguminous plants. In return these bacteria gets the food like carbohydrates produce by the plants
        
             
        
        
        
Hello! :)
The eroded material finds its way to the bottom of oceans because of gravity (from... According to the hypsometric curve (plot between elevation and % of earth's surface), only about 29% of Earth's surface is above the mean sea level, rest 71% has an elevation less than mean sea level.
Hope this helped and I hope I answered in time!
~ Destiny ^_^