Tag: gm crops

Questions Related to gm crops

Rennin used in cheese industry is a/an

  1. Antibiotic

  2. Enzyme

  3. Alkaloid

  4. Inhibitor


Correct Option: B
Explanation:

Chymosin, known also as rennin, is a proteolytic enzyme synthesized by chief cells in the stomach in young ruminants. Its role in digestion is to curdle or coagulate milk in the stomach, in the very young animal. Chymosin efficiently converts liquid milk to a semisolid like cottage cheese, allowing it to be retained for longer periods in the stomach. It is widely used in the production of cheese. 

Beer is obtained from

  1. Molasses

  2. Grapes

  3. Barley

  4. Rye


Correct Option: C
Explanation:

Beer is an alcoholic beverage produced by the saccharification of starch and fermentation of the resulting sugar. The starch and saccharification enzymes are often derived from malted cereal grains, most commonly malted barley and malted wheat.

First fermented acid is

  1. Gluconic acid

  2. Lactic acid

  3. Fumaric acid

  4. All of the above


Correct Option: B
Explanation:

Lactobacillus bacteria have the ability to convert sugars into lactic acid. The Lactobacillus strain is so named because it was first studied in milk ferments. These bacteria readily use lactose or other sugars and convert them quickly and easily to lactic acid.

Which one of the following is used in industrial preparation of ethanol?

  1. Lactobacillus

  2. Azotobacter

  3. Penicillium

  4. Saccharomyces


Correct Option: D
Explanation:
Yeast are simple unicellular organisms belonging to the Kingdom Fungi. The alcoholic fermentation is conducted by yeast of the genus Saccharomyces. The two common species involved are S. cerevisiae and S. bayanus. Saccharomyces converts the glucose, fructose and sucrose found in grape must and juice into ethanol via the process of fermentation. In fermentation, an organic compound, in this case acetaldehyde, serves as terminal electron acceptor. This leads to the production of ethanol.

Vitamin ${B} _{12}$ is formed during fermentation of

  1. Ashbya gossypii

  2. Rhizopus stolonifer

  3. Propionibacteria

  4. Saccharomyces cerevisiae


Correct Option: C
Explanation:
Vitamin B$ _{12}$ is one of the important vitamins of B complex group. It is also known as cobalamin or cobamide. 
Direct fermentation employing Bacillus megaterium, Propionibacterium freudenreichii, Propionibacterium shermanii and Pseudomonas is used for commercial production of vitamin B$ _{12}$. 

Citric acid is produced by

  1. Aspergillus niger

  2. Streptococcus lactis

  3. Acetobacter syboxydans

  4. Candida utilis


Correct Option: A
Explanation:

Aspergillus niger is a fungus and one of the most common species of the genus Aspergillus. Various strains of A. niger are used in the industrial preparation of citric acid and gluconic acid.

Saccharomyces cerevisiae is used in the formation of

  1. Ethanol

  2. Methanol

  3. Acetic acid

  4. Antibiotics


Correct Option: A
Explanation:

S. cerevisiae is known for its role in food production. It is the critical component in the fermentation process that converts sugar into ethyl alcohol (ethanol), an ingredient shared in beer, wine and distilled beverages. It is also used in the baking process as a leavening agent; yeast releasing gas into their environment results in the spongy-like texture of breads and cakes. 

Which of the following is used to manufacture ethanol from starch?

  1. Penicillin

  2. Saccharomyces

  3. Azotobactor

  4. Lactobacillus


Correct Option: B
Explanation:

S. cerevisiae is known for its role in food production. It is the critical component in the fermentation process that converts sugar into ethyl alcohol (ethanol), an ingredient shared in beer, wine and distilled beverages. It is also used in the baking process as a leavening agent; yeast releasing gas into their environment results in the spongy-like texture of breads and cakes. 

During the formation of bread, it becomes porous due to release of CO$ _{2}$ by the action of

  1. Yeast

  2. Bacteria

  3. Virus

  4. Protozoan


Correct Option: A
Explanation:

In a bread dough, where the oxygen supply is limited, the yeast can only partially breakdown the sugar. Alcohol and carbon dioxide are produced in this process known as alcoholic fermentation. The carbon dioxide produced in these reactions causes the dough to rise, and the alcohol produced mostly evaporates from the dough during the baking process. During fermentation, each yeast cell forms a centre around which carbon dioxide bubbles form. Thousands of tiny bubbles, each surrounded by a thin film of gluten form cells inside the dough piece. The increase in dough size occurs as these cells fill with gas.

Thus, the correct answer is option A.

Which one is not used in the production of yogurt?

  1. Streptococcus lactis

  2. Streptococcus thermophilous

  3. Lactobacillus bulgaris

  4. Acetobacter aceti


Correct Option: D
Explanation:

Yogurt is a food produced by bacterial fermentation of milk. The bacteria used to make yogurt are known as yogurt cultures. Fermentation of lactose by these bacteria produces lactic acid, which acts on milk protein to give yogurt its texture and its characteristic tang. Some representative strains of yogurt cultures are Streptococcus lactis, S. cremoris, S. thermophilus, Lactobacillus bulgaricus, L. acidophilus, and L. plantarum.