| 61 |
For an acetic acid buffer (pKa = 4.76), what is the pH when the salt-to-acid ratio is 10? |
Agriculture
pH and buffers |
Hard |
| 62 |
The main buffer system that keeps blood pH near 7.4 is the: |
Agriculture
pH and buffers |
Medium |
| 63 |
Lactose, the sugar of milk, is made of: |
Agriculture
Biomolecules |
Easy |
| 64 |
The bond linking amino acids in a protein is the: |
Agriculture
Biomolecules |
Easy |
| 65 |
Which vitamin is water-soluble? |
Agriculture
Biomolecules |
Medium |
| 66 |
Deficiency of vitamin B₁ (thiamine) causes: |
Agriculture
Biomolecules |
Medium |
| 67 |
Amylase, which breaks down starch using water, belongs to which enzyme class? |
Agriculture
Biomolecules |
Hard |
| 68 |
The main storage carbohydrate in plants is: |
Agriculture
Biomolecules |
Easy |
| 69 |
The fungal cell wall is mainly made of: |
Agriculture
Micro-organisms |
Easy |
| 70 |
Rod-shaped bacteria are called: |
Agriculture
Micro-organisms |
Easy |
| 71 |
The antibiotic streptomycin is obtained from: |
Agriculture
Micro-organisms |
Medium |
| 72 |
Which feature is true of viruses? |
Agriculture
Micro-organisms |
Medium |
| 73 |
Anabaena and Nostoc, which fix nitrogen in rice fields, are best classed as: |
Agriculture
Micro-organisms |
Hard |
| 74 |
Conversion of ammonium to nitrite in soil is carried out by: |
Agriculture
Role of micro-organisms |
Easy |
| 75 |
The products of yeast fermentation of glucose are: |
Agriculture
Role of micro-organisms |
Easy |
| 76 |
Which organism fixes nitrogen while living freely in the soil, without a host plant? |
Agriculture
Role of micro-organisms |
Medium |
| 77 |
Wheat straw added to soil decomposes slowly mainly because it has a: |
Agriculture
Role of micro-organisms |
Hard |
| 78 |
Loss of soil nitrogen as N₂ gas under waterlogged conditions is called: |
Agriculture
Role of micro-organisms |
Medium |
| 79 |
The setting of milk into curd is due to: |
Agriculture
Role of micro-organisms |
Easy |
| 80 |
The single cotyledon of a maize grain is called the: |
Agriculture
Seed structure |
Easy |