Biology - Study Mode
[#921] The bacterium which reduces the fertility of soil is
Correct Answer
(D) Bacillus dentificans
Explanation
Solution: Bacillus dentificans is the bacterium which reduces the fertility of soil.
[#922] They are used in the retting of flax and hemp.
Correct Answer
(B) Bacteria
Explanation
Solution: Bacteria are used in the retting of flax and hemp.
[#923] Which of the following bacteria is responsible for the formation of curd?
Correct Answer
(C) Lacto-bacillus
Explanation
Solution: The preparation of curd requires a lactobacillus bacteria, while yogurt is made using two specific strains of bacteria called Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus bacteria. Other strains of lactic acid bacteria may also be added.
[#924] Yeast used in making bread is a
Correct Answer
(A) Fungus
Explanation
Solution: Baker's yeast is the common name for the strains of yeast commonly used in baking bread and bakery products, serving as a leavening agent which causes the bread to rise (expand and become lighter and softer) by converting the fermentable sugars present in the dough into carbon dioxide and ethanol. It is a fungus.
[#925] Nitrogen fixation process in the soil is done by
Correct Answer
(B) Bacteria
Explanation
Solution: Most nitrogen fixation occurs naturally, in the soil, by bacteria.