This set of Fermentation Technology test focuses on “Morphology, Cytology and Cellular Function of Brewing Yeast”.
1. Who described the cell morphology of S. cerevisiae?
Explanation: Lodder in 1970 described the morphology of S. cerevisiae. He described the cells as being spheroidal, subglobose, ovoid, ellipsoidal or cylindrical to elongate, single in pairs, occasionally in short chains or clusters.
2. The effect of ploidy on yeast cells was demonstrated by _______________
Explanation: Vagvaolgyi et al. in 1988 demonstrated the effect of ploidy on yeast cells size being 4.2, 5.2, 5.9 µm in diameter of haploid, diploid, and triploid respectively.
3. Which of the following component is present in the highest percentage of the dry weight of dried wine yeast?
Explanation: Carbon is present in the highest percentage of the dry weight of dried wine yeast with 48.2%. Iron is 0.005%, Sulphur is 0.01% and Oxygen is 33.8%. This molecular composition was given by Rosen in 1989.
4. Which of the following macromolecule is present in the lowest amount in bakers’ yeast?
Explanation: Moisture is present in the lowest amount of 2-5% in bakers’ yeast. DNA and RNA are 6-8%, Minerals are 7-8% and lipids are 4-5% of the total macromolecular composition. Protein is present in the highest percentage with 42-46%. This macromolecular composition was given by Reed and Nagodarithana in 1991.
5. Spent yeast is used as ______________
a) Nutritional supplement
b) Dietary supplement
c) Water supplement
d) Air supplement
Explanation: Spent yeast is used as a nutritional supplement because it is an excellent source of vitamins. After fermentation, there is always leftover yeast in the form of sludge at the bottom of the fermentation vessel. The leftover yeast is referred to as spent yeast.
6. Which of the following forms the barrier between the cytoplasm and the external environment?
b) Plasma membrane
Explanation: Plasma membrane forms the barrier between the cytoplasm and the external environment. It acts as a semi-permeable membrane which allows only specific solutes to pass into the cytoplasm of the cell.
7. The plasma membrane is composed of _______________
a) Carbohydrate bilayer
b) Protein bilayer
c) Lipid bilayer
Explanation: The plasma membrane is composed of the lipid bilayer of proteins. It constitutes of two layers of fat cells organized in two sheets. The lipid and protein molecules are held together by hydrogen bonding and are amphipathic in nature which stabilizes the lipid bilayer.
8. Which of the following describes the space between the plasma membrane and cell wall?
a) Plasma membrane
Explanation: Periplasm is the space between the outer surface of the plasma membrane and the inner surface of the cell wall. It is discontinuous space because of invaginations in the plasma membrane and irregularities in the cell wall.
9. Who defined periplasmic enzymes?
Explanation: Arnold in 1991 defined periplasmic enzymes as those which are assayed in intact cells without the disruption of the plasma membrane. Enzymes associated with periplasmic space are mostly invertase and acid phosphatase.
10. Which of the following is not correct for mitochondria?
a) It is a double-membrane organelle
b) It synthesizes its own DNA
c) It synthesizes proteins
d) The powerhouse of the cell
Explanation: Mitochondria is regarded as the powerhouse of the cell as it helps in the production of ATP. It also synthesizes its own DNA that is why it is also known as an autonomous organelle. It is protected by a double-walled membrane: inner and outer membrane.
11. The membrane of vacuole is known as ____________
b) Plasma membrane
c) Cell wall
Explanation: The membrane of the vacuole is known as tonoplast. It surrounds the large vacuole in the cell and is also called a vacuolar membrane. It separates vacuoles from the cytoplasmic environment and is used to take food substrates and dissolve them.
12. Which of the following is responsible for the synthesis of proteins?
d) Golgi body
Explanation: Ribosomes are responsible for the synthesis of proteins. They are responsible for the binding of messenger RNA (mRNA) and transfer RNA (tRNA) to synthesize polypeptide chains and proteins.
13. The SER consists of ribosomes.
Explanation: The Rough Endoplasmic Reticulum (RER) consists of the ribosome, that is, ribosomes are bound to the endoplasmic reticulum. This roughens the surface of endoplasmic reticulum and forms Rough Endoplasmic Reticulum. Whereas the SER does not contain ribosomes, that is why they are smoother in appearance.
14. The chloroplast is an autonomous organelle.
Explanation: Chloroplast is an autonomous organelle which synthesizes its own DNA and proteins required for their functioning. It is a green coloured pigment which is mainly present in plants and is responsible for performing photosynthesis.
15. Which of the following is not a single membrane-bound organelle?
a) Endoplasmic Reticulum
b) Golgi Apparatus
Explanation: Endoplasmic Reticulum, Golgi Apparatus, Lysosomes are bounded by a single membrane and are called as single-membrane bound organelles. Whereas mitochondria and chloroplast are bounded by a double membrane and are called as double-membrane bound organelles.
Sanfoundry Global Education & Learning Series – Fermentation Technology.
To practice all areas of Fermentation Technology for tests, here is complete set of 1000+ Multiple Choice Questions and Answers.