Discussion
Arrange the steps of producing ethanol from a lignocellulosic residue in order:
1. Enzymatic hydrolysis to fermentable sugars
2. Pretreatment to open up the lignin barrier
3. Distillation and dehydration of the ethanol
4. Fermentation of the sugars by yeast
Select the correct sequence.
Answer: C
Correct answer: 2, 1, 4, 3
The order is fixed by what each step needs from the last. Pretreatment comes first (2) to open the lignin barrier, since without it the enzymes cannot reach the cellulose at all.
Enzymatic hydrolysis then releases fermentable sugars (1), the yeast ferments them to ethanol (4), and distillation with dehydration recovers and dries the product (3). The first two steps are what distinguish this route from molasses fermentation, and they are the reason it costs so much more.
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development