Answer:
Biogas is composed mostly of methane (CH4), the same compound in natural gas, and carbon dioxide (CO2).
Explanation:
 
        
             
        
        
        
B and C)
They often obtain most of their nutrients through the cell membrane as diffusion is able to take place passively and so at no energy loss to the organism, this can be essential for a single celled organism as they are able to produce a lot less energy due to having fewer mitochondria in comparison to multicellular organisms. 
They also require few resources as single celled organisms are very small and so require only a small amount of raw resources for respiration because they have a small energy demand to meet.
        
             
        
        
        
Other things veterinarians are looking at is the boundary between animals, people, and the environment. Veterinarians need to work with human doctors to work on food safety, problems connected to cancer, etc. Veterinarians and human doctors can get facts from each other. The problems we face in society means that they have to cooperate with both the animal health side, the human health side, and environment side as well. One way they think of “one health” is evolving viruses. They are looking at this to find a solution by the use of comparative medicine and observing the environment.
        
             
        
        
        
Answer:
Anaphase I
Explanation:
In anaphase I, the homologous chromosomes are pulled apart and move to opposite poles.