Question 1
Ale strains of Saccharomyces cerevisiae cannot easily ferment ______________
A. Fructose
B. Trehalose
C. Sucrose
D. Raffinose
View Answer
Answer: Option B
Explanation:
Ale strains of Saccharomyces cerevisiae can ferment glucose, fructose, maltose, sucrose, galactose, raffinose, maltotriose. They cannot ferment trehalose easily. Lager strains of Saccharomyces cerevisiae are also able to ferment melibiose. Therefore, there is some variability between individual strains.
Question 2
Bioaccumulation is a faster process.
A. True
B. False
View Answer
Answer: Option B
Explanation:
Bioaccumulation is a slower and well-regulated process. However, it is dependent on temperature and is blocked by metabolic inhibitors. Many genes have been identified which appear associated with the uptake of metal ions. An example is a FRE1 gene.
Question 3
Biosorption is a ____________ process.
A. Active
B. Passive
C. Controlled
D. Feedback
View Answer
Answer: Option B
Explanation:
Biosorption is a passive process in which the metal ions become attached to the cell wall. It is however rapid, insensitive to temperature, and does not require metabolic energy. It is also not inhibited by the metabolic inhibitors.
Question 4
Glycine belongs to _____________ in order of assimilation during fermentation.
A. Class A
B. Class B
C. Class C
D. Class D
View Answer
Answer: Option C
Explanation:
Glycine belongs to Class C amino acid. Tyrosine, tryptophan, Alanine, Phenylalanine, etc. belong to class C amino acid. Glycine is an amino acid that contains single H-bond as a side chain. It is a proteingenic amino acid.
Question 5
Proline is a class 1 wort amino acid based on the effect of fermentation performance.
A. True
B. False
View Answer
Answer: Option A
Explanation:
Proline is a class 1 wort amino acid based on the effect of fermentation performance. Proline is a proteingenic amino acid that is involved in the biosynthesis of proteins. It is non-essential amino acid to human beings.
Question 6
SUC2 helps in the hydrolyzes of _____________
A. Sucrose and Glucose
B. Maltose and Sucrose
C. Sucrose and Raffinose
D. Glucose and Maltose
View Answer
Answer: Option C
Explanation:
In Saccharomyces cerevisiae, the enzyme encoded by the SUC2 gene and it helps in the hydrolyzes of sucrose and raffinose. After hydrolyzes, fructose and glucose are taken up via glucose transporters.
Question 7
SUT1 gene is involved in _______________
A. Sterol uptake
B. Carbohydrate uptake
C. Protein uptake
D. Metal ion uptake
View Answer
Answer: Option A
Explanation:
The product of SUT1 gene is involved in the sterol uptake. Bourot and Karst in 1995 isolated a SUT1 from yeast and provided evidence that it is involved in sterol uptake under conditions of anaerobiosis, or in the absence of haem biosynthesis.
Question 8
What do you mean by aerobic sterol exclusion?
A. High uptake occurs
B. No uptake occurs
C. Low uptake occurs
D. Moderate uptake occurs
View Answer
Answer: Option B
Explanation:
Aerobic sterol means no uptake occurs. Under anaerobic conditions, no uptake occurs in the stationary phase. This was termed by Lewis et al. in 1998.
Question 9
Which of the following carbohydrate is assimilated first?
A. Sucrose
B. Maltotriose
C. Glucose
D. Fructose
View Answer
Answer: Option A
Explanation:
Sucrose is utilized first and the hydrolysis causes an increase in the concentration of fructose. Fructose and Glucose are taken up more or less simultaneously and is disappeared from wort within 24 hours. After glucose, maltose is assimilated and at last, after maltose, maltotriose is utilized.
Question 10
Which of the following is a Class A amino acid?
A. Histidine
B. Lysine
C. Leucine
D. Proline
View Answer
Answer: Option B
Explanation:
Lysine is a class A amino acid. Some of the other class A amino acids are Arginine, Aspartic acid, Glutamate, Serine. Histidine and Leucine are Class B amino acids and Proline is a class D amino acid in order of assimilation during fermentation.
Question 11
Which of the following is not utilized by the brewing strains?
A. Dextrins
B. Starch
C. Maltotriose
D. Melibiose
View Answer
Answer: Option A
Explanation:
Higher polysaccharides, the dextrins are not utilized by the brewing strains and these contribute to beer flavor by way of imparting fullness. Although many attempts have been made to utilize dextrins.
Question 12
Who concluded the patterns of loss of glucose?
A. Maurico and Salmon
B. Does and Bilson
C. Bisson and Fraenkel
D. Vakeria and Hinchliffe
View Answer
Answer: Option A
Explanation:
Maurico and Salmon in 1992 concluded the differential patterns of loss of glucose transporters due to nitrogen starvation formed the basis of differences in ethanol productivity in two strains of S.cerevisiae.
Question 13
Who introduced the first method of dextrin utilization?
A. Vakeria and Hinchliffe
B. Oura
C. Bisson and Fraenkel
D. Does and Bisson
View Answer
Answer: Option A
Explanation:
Vakeria and Hinchliffe introduced the first method for the utilization of dextrins. They introduced an appropriate enzyme into the brewing yeast by genetic manipulations. These modifications lead to the utilization of dextrin.
Question 14
Who recognized different amino acid transport systems in yeast?
A. Bilson
B. Maurico
C. Grenson
D. Horak
View Answer
Answer: Option D
Explanation:
Horak in 1986 recognized 16 different amino acid transport systems in yeast. Of these 12 are constitutive and remaining are subject to regulation by the nitrogen sources present in the growth medium. This phenomenon is termed as nitrogen catabolic repression.