Tag: biotechnology

Quizzes (4) Questions (393)

Questions Related to biotechnology

Multiple choice biology biotechnology and genetic engineering stds and infertility gm crops biotechnology

Vitamin $B _{12}$ is synthesized by

  1. Saccharomyces

  2. Acetobacter

  3. Agaricus

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Plants and animals do not have the capacity to synthesize vitamin B12 by their own. But the microorganisms like Saccharomyces cerevisiae ( contains vitamin B12 but there is no clear answer about the source of synthesizing vitamin B12 in this yeast. But it synthesizes vitamin B12.), acetobacter and also by the mushrooms Agaricus. Thus, the correct answer is option D.

Multiple choice biology biotechnology and genetic engineering stds and infertility gm crops biotechnology

In cheese manufacture, the micro-organisms are used for

  1. The souring of milk only

  2. The ripening only

  3. Both A and B

  4. Development of resistance to spoilage
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The curdling step in cheese making relies on lactic acid bacteria. These bacteria are able to ferment the carbohydrates found in the milk, releasing lactic acid in the process. The lactic acid causes the proteins dissolved in the milk to precipitate, or come out of solution. When the proteins precipitate, they pull out the fats as well. What you are left with is similar to the sour milk from the introduction: the liquid whey filled with many solid chunks of protein and fat, called curds.

Yeasts and molds are used in some cheeses to provide the characteristic colours and flavours of some cheese varieties. Torula yeast is used in the smear for the ripening of brick and limberger cheese. Examples of molds include Penicillium camemberti in camembert and brie, and Penicillium roqueforti in blue cheeses.
Thus, the correct answer is option C.

Multiple choice biology biotechnology and genetic engineering stds and infertility gm crops biotechnology

Conversion of sugar into alcohol during fermentation is due to the direct action of

  1. Temperature

  2. Microorganism

  3. Zymase

  4. Concentration of sugar solution
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The overall process of fermentation is to convert glucose sugar (C$ _6$H$ _{12}$O$ _6$) to alcohol (CH$ _3$CH$ _2$OH) and carbon dioxide gas (CO$ _2$). The reactions within the yeast to make this happen are very complex but the overall process is as follows: 

C$ _6$H$ _{12}$O$ _6$ ==> 2(CH$ _3$CH$ _2$OH) + 2(CO$ _2$) 
Sugar ==> Alcohol + Carbon dioxide gas. 
The most important type of fermentation is alcoholic fermentation, in which the action of zymase secreted by yeast converts simple sugars, such as glucose and fructose, into ethyl alcohol and carbon dioxide.

Multiple choice biology biotechnology and genetic engineering stds and infertility gm crops biotechnology

Rennin used in cheese industry is a/an

  1. Antibiotic

  2. Enzyme

  3. Alkaloid

  4. Inhibitor
Reveal answer Fill a bubble to check yourself
B Correct answer
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. 

Multiple choice biology biotechnology and genetic engineering stds and infertility gm crops biotechnology

First fermented acid is

  1. Gluconic acid

  2. Lactic acid

  3. Fumaric acid

  4. All of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
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.

Multiple choice biology biotechnology and genetic engineering stds and infertility gm crops biotechnology

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

  1. Lactobacillus

  2. Azotobacter

  3. Penicillium

  4. Saccharomyces
Reveal answer Fill a bubble to check yourself
D Correct answer
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.
Multiple choice biology biotechnology and genetic engineering stds and infertility gm crops biotechnology

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

  1. Ashbya gossypii

  2. Rhizopus stolonifer

  3. Propionibacteria

  4. Saccharomyces cerevisiae
Reveal answer Fill a bubble to check yourself
C Correct answer
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}$. 
Multiple choice biology biotechnology and genetic engineering stds and infertility gm crops biotechnology

Saccharomyces cerevisiae is used in the formation of

  1. Ethanol

  2. Methanol

  3. Acetic acid

  4. Antibiotics
Reveal answer Fill a bubble to check yourself
A Correct answer
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.