During anaerobic digestion of organic waste, such as in producing biogas, which one of the following is left undegraded :-
- Lignin
- Cellulose
- Hemi-cellulose
- Lipids
Answer
(1) Lignin
Solution
As per NCERT, methanogens such as Methanobacterium grow anaerobically on cellulosic material and produce methane along with CO2 and H2.
⇒ Cellulose, hemicellulose and lipids are broken down by anaerobic bacteria during biogas production.
⇒ Lignin is a complex aromatic polymer that is degraded mainly by aerobic fungi; it is not broken down under anaerobic conditions.
∴ Lignin is left undegraded.
Answer: (1)