Answer:
A pollen tube grows from the pollen grain into the ovary 
Explanation:
Water is needed for fertilization in several plant groups because the sperm needs to swim to meet the non-motile eggs of the female organs. 
<em>However in angiosperms, the pollen germinates and a structure known as pollen tube which contains the male gametophyte (sperm) grows into the ovary where the ovule is located and the male gametophyte is deposited in the ovule to initiate the fertilization process.</em>
<em>Hence, water is really not necessary for fertilization in the angiosperms.</em>
 
        
                    
             
        
        
        
Natrual variations i think 
        
                    
             
        
        
        
Answer:
It is important to use the regulatory sequence of a milk gene when constructing a recombinant gene used to produce a human protein secreted in milk because<em> it is capable of increasing or decreasing the expression of specific genes within an organism.</em>
Explanation:
<em>Regulatory Sequence</em> is<em> a segment of a nucleic acid molecule</em> which is capable of increasing or decreasing the expression of specific genes within an organism. Regulation of gene expression is an essential feature of all living organisms and viruses.