Answer:
Zika virus and West Nile virus are the two pathogens which causes more diseases due to increase the population of mosquito.
Explanation:
Zika virus belongs to the family of Flaviviridae. Aedes mosquitoes which are active at day time are the carrier of this virus. West Nile virus is also spread through the bite of mosquito. The infected mosquito is the main cause of spreading of this disease. This virus is spreading too fast in the United States of America in the summer season where the population of mosquitoes increases.
 
        
             
        
        
        
All other organs, ducts, and glands in the reproductive system are considered secondary, or accessory, reproductive organs. These structures transport and sustain the gametes and nature the developing offspring. 
Hope this helps!
        
                    
             
        
        
        
The correct answer is (a.) a mutation of the hemoglobin allowing better oxygen-carrying capacity. The mutation of the hemoglobin that allows a better oxygen-carrying capacity would be the most beneficial to an elephant and its descendants. 
        
             
        
        
        
The answer is A. When a potent drug is discovered, it has to undergo animal and human trials to test it ADMET (Absorption, Distribution Metabolism, Excretion, and Toxicity) properties. Using tissue cultures to test drugs, such as cancer drugs, prevents the incidence of subjecting humans to the unknown adverse effects of the drugs before the drugs are determined to be safe for use.