Answer: Viruses, although not living things, do show some characteristics that they are living. Because they can't reproduce by themselves (without a host), viruses are not considered living. They are made of proteins and glycoproteins like cells are. They contain genetic information needed to produce more viruses in the form of DNA or RNA.
They are acellular, that is, they contain no cytoplasm or cellular organelles. They carry out no metabolism on their own and must replicate using the host cell's metabolic machinery.
Answer:
Archaebacteria
Explanation:
Carl Woese categorised the bacteria into two domains called the Archaebacteria and the Eubacteria.
The Archaebacteria is the group of bacteria which can survive in the extreme condition as they posses the characteristics of both the prokaryotes and some eukaryotes. The bacteria are known as the extremophiles.
In the given question, the bacteria which lives in the gut of the human uses methane gas and thus are known as the methanobacteria. These bacteria are considered the archaebacteria as they methane for survival.
Thus, Archaebacteria is correct.
Cellulose is a carbohydrate which is present in the plant cells. The cellulose is a polymer with glucose as the monomer units. The monomer units of cellulose is attached by the beta linkages. The cellulose provides structural support to the plant cells by forming micro-tubules. The humans cannot eat the diet rich in cellulose because they lack the enzymes that are needed to digest them. Some animals, such as cows and termites have these enzymes but not the humans.
Hence, the answer is 'people cannot digest cellulose'.
