Answer:d.are eventually replaced by electrons from photosytem 11
Explanation:there are two photosystems in the photosynthetic process.PSI and PS II. PS I has a reaction center called P700 because it's chlorophyll has a maximum absorption of 700nm wavelength.PSII has a reaction center called P680nm for similar reason.when an excited electron is transferred to P700,it becomes excited.this electron is passed down from from acceptor to another, until it is used to reduce NADP+ to NADPH.this electron is replaced when P680 gets excited by a photo of light and splits water to release electrons , protons and Oxygen 
 
        
             
        
        
        
True that should be the answer
        
                    
             
        
        
        
Answer:
<em>The correct option is C) AS</em>
Explanation:
Sickle cell anaemia is a recessive disorder in which the blood of the person is not able to clot properly. For sickle cell to occur, both the alleles for the trait have to be recessive. A person who has a dominant and a recessive allele will be heterozygous, showing the dominant characteristics. But such a person will be a carrier for the disease. There will be chances for the offsprings of that person to actually have the disease. 
 
        
             
        
        
        
Answer: Portrayal of thermal convection as a mechanism.
if its not right im srry :( 
but if it is your welcome :D