*The key function of each of the two photosystems is to absorb light and convert the energy of the absorbed light into redox energy, which drives electron transport.
In PS II (the first photosystem in the sequence), P680 is oxidized (which in turn oxidizes water), and the PS II primary electron acceptor is reduced (which in turn reduces the electron transport chain between the photosystems).
In PS I, the PS I primary electron acceptor is reduced (which in turn reduces other compounds that ultimately reduce NADP+ to NADPH), and P700 is oxidized (which in turn oxidizes the electron transport chain between the photosystems).
 
        
             
        
        
        
Cellulose is another long polymer of glucose. Plant cells make their cell walls out of cellulose. In fact, 100 billion tons of cellulose is made every year on earth. Cellulose is indigestible in most animals, including us. Ever eat a cardboard box? You get the picture. We simply lack cellulase, the enzyme that can break it down. Some bacteria, some single-celled protists, and fungi have the enzyme. Animals that feed on cellulose harbor these microbes that help them digest it. Even though, we cannot break down this molecule, we do need cellulose in our diet. We call it “fiber”. Cellulose stimulates the colon to produce regular bowel movements and helps make the stools large and soft. A diet rich in fiber can prevent a painful intestinal disorder called diverticulosis. Hard impacted stools can sometimes cause the walls of the colon to form blind outpockets called diverticula which can periodically inflame. So what makes cellulose different from starch? Isn’t it made of glucose? Well it is but the glucose monomers are organized in an interesting fashion. The orientation of the glucose molecules alternates. So if the first one is right side up, the next one is upside down and then the next is right side up and the next one is upside down. Apparently this is a tricky arrangement for an enzyme to break.
        
             
        
        
        
Answer:
This question is incomplete as there is no figure in the question but the compound in the figure is Ethanoic acid (CH3COOH). Hence, we can calculate the mass. 
The answer is: 30grams
Explanation:
According to the question, the volume of the compound (CH3COOH) is 1litre while the molar concentration is 0.5M
Molarity or Molar concentration is calculated using the formula:
M= n/V
Where; M= Molarity (M) = 0.5M
 n= number of moles (mol)
 V= Volume (V) = 1L
Hence, number of moles (n) = M × V
n = 0.5 × 1
n = 0.5 moles. 
To calculate the mass in grams of CH3COOH, we say;
Number of moles (n) × molar mass (MM)
Since atomic mass for (C= 12, H= 1 and O=16)
Molar mass of CH3COOH:
= 12 + 1(3) + 12 + 16 + 16 + 1
Molar mass of CH3COOH = 60g/mol
Mass (in grams) of CH3COOH = 0.5 moles × 60g/mol
Mass = 30grams.
Therefore, 30grams of CH3COOH compound are required to make 1 liter of a 0.5 M solution.
 
        
             
        
        
        
The matching DNA strand would be A - T, G - C, A -T, A - T, C - G, or in other words TCTTG (because you had the strand AGTAAC). 
Always remember that A pairs with T, G pairs with C, T obviously pairs with A, and C obviously with G.