<span>Actually some of the important causes for the age related drop in female fertility is due to some chronic bad habits like chain smoking, regular alcohol intake and taking big dose of drugs, and also due to wrong diet or junky bad food habits, then mainly its due to hormone imbalance problems.</span>
        
             
        
        
        
<span>Out of the following given choices;</span>
A. Further antibody attack. 
B. Phagocytosis 
C. Helper T cells 
D. B cells. 
E. None of the above.
The answer
is B. Phagocytises is the engulfment of a particle from the external
environment, by a cell, for ingestion. This is especially critical for the
function of macrophages, which are immune cells. These macrophages have receptors
for the Fc region of the immunoglobulin on their cell membrane surface. 
 
        
             
        
        
        
Answer:
C. CH4 + 202 – CO2 + 2H20
Explanation:
CH4+O2-CO2+H20
The above equation represents combustion of methane to produce carbon-dioxide and water.
One carbon atom is present on the reactant side as well as on the product side. Four hydrogen atoms are present on the reactant side  and two hydrogen atoms on product side. In order to balance this equation, we would multiply water molecule by two. Now there are four atoms of oxygen in the product side but only two on reactant side, so we will multiply oxygen molecule by two on the reactant side. Now the equation is balanced.
The balanced chemical equation is:
CH4+202-CO2+2H2O
This equation obeys the law of conservation of mass as the mass of the reactants is same as that of the products.
 
        
             
        
        
        
So what would happen if photosynthesis suddenly stopped happening? If photosynthesis came to an abrupt end, most plants would die within short order. ... That's because for photosynthesis to cease to exist, Earth would have to plunge into darkness.