Bacteriophages are viruses that infect and duplicate within a bacterium. Temperate phages (such as lambda phage) can keep reproducing using both the lytic and the lysogenic cycle.  
SO.... Bacteriophages  
I believe is the answer that you are looking .
Let me know if its right or wrong!!
 
        
             
        
        
        
Answer:
c. A to K 
Explanation:
If the alanine mutation is restored to K or lysine residue, most likely the wild type level of activity can be restored. This is because, arginine and lysine have -NH2 as the functional group. So, functional similarity of arginine can be expected from lysine as well.
Hence the correct option is c that is A to K. 
 
        
             
        
        
        
The answer to this question would be: B<span>. It relaxes blood vessels in Harvey’s penis, allowing them to expand. 
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Viagra active component is sildenafil citrate which has the ability to relax the smooth muscle in the artery and dilate the arteries of the penis. As the arteries in penis dilate, the blood flow into penis will be increased. This will make penis filled with blood and give pressure to nearby veins causing them to close. All this event cause increased pressure in penis that was making the erection
        
             
        
        
        
Answer:
Sheep and goats are important livestock species in developing countries. Of the world's 1,614million sheep and 475 million goats, 65% and 95%, respectively, are located in developing countries. Fifty-three percent of the total small-ruminant population in the developing countries is found in Asia, particularly in India and Pakistan, 33% in Africa, and 14% in Latin America (FAO, 1984).
Goats are hardy and well-adapted to harsh climates. Due to their grazing habits and physiological characteristics, they are able to browse on plants that would normally not be eaten by other livestock species. Thus, the presence of goats in mixed species grazing systems can lead to a more efficient use of the natural resource base and add flexibility to the management of livestock. This last characteristic is especially desirable in fragile environments.
Sheep and goats contribute to a broad range of production systems. The most common system throughout the developing countries involve either the extensive system with large herds and/or flocks grazing on arid and semi-arid rangelands or the intensive system with smaller herds and/or flocks kept in confinement, mostly in the humid tropics.