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This section includes 533 Mcqs, each offering curated multiple-choice questions to sharpen your Dairy Engineering knowledge and support exam preparation. Choose a topic below to get started.
351. |
Microaerophilic bacteria require low levels of oxygen for growth. |
A. | True |
B. | False |
C. | May be |
D. | Can't say |
Answer» B. False | |
352. |
Mesophiles are group of bacteria that grow within the temperature range of? |
A. | 0-20 degree Celsius |
B. | 25-40 degree Celsius |
C. | 45-60 degree Celsius |
D. | more than 60 degree Celsius |
Answer» C. 45-60 degree Celsius | |
353. |
A piece of DNA, having ability to move from one site to another, either between DNA's of plasmids, bacterias, bacteriophages or within DNA molecule, is called |
A. | Vector |
B. | Transposons |
C. | Plasmid |
D. | Template |
Answer» C. Plasmid | |
354. |
In which of the following, lipo-polysaccharide is a major constituent of outer membrane of the cellwall? |
A. | Gram-positive bacteria |
B. | Gram-negative bacteria |
C. | Fungi |
D. | None of these |
Answer» C. Fungi | |
355. |
Which of the following is a rich source of B vitamins? |
A. | Peptone |
B. | Yeast extract |
C. | Beef extract |
D. | Agar |
Answer» C. Beef extract | |
356. |
Which of the following is not true about peptidoglycan? |
A. | It is a polymer consisting of N-acetyl glucosamine, N-acetyl muramic acid and amino acids (alanine, lysine, etc.) |
B. | It is present in prokaryotic cell wall |
C. | It occurs in the form of a bag shaped macro molecule surrounding the cytoplasm membrane |
D. | None of the above |
Answer» E. | |
357. |
In eukaryotic cells, ribosomes are |
A. | 70S |
B. | 60S |
C. | 80S |
D. | Not specific |
Answer» D. Not specific | |
358. |
In the growth equation: n= 3.3 (log10 N – log10 No ), n stands for____________ |
A. | total population |
B. | initial population |
C. | number of generations |
D. | growth constant |
Answer» D. growth constant | |
359. |
Which of the following is used as a solidifying agent for media? |
A. | Beef extract |
B. | Peptone |
C. | Agar |
D. | Yeast extract |
Answer» D. Yeast extract | |
360. |
Name the component of flagellum. |
A. | Filament |
B. | Hook |
C. | Basal body |
D. | All of these |
Answer» E. | |
361. |
What is approximate number of genes in human in contrast to 'prokaryotes' ? |
A. | 100000 |
B. | 1000000 |
C. | 10000 |
D. | 200000 |
Answer» B. 1000000 | |
362. |
Which of the following structure(s) is /are external to cell wall? |
A. | Flagella |
B. | Stalks |
C. | Sheath |
D. | All of these |
Answer» E. | |
363. |
Site for nutrients in 'cytoplasm' is |
A. | Vacuole |
B. | Food vacuole |
C. | Granules |
D. | Cytosol |
Answer» D. Cytosol | |
364. |
Which of the following is used to grow bacterial culture continuously? |
A. | Chemostat |
B. | Hemostat |
C. | Coulter-Counter |
D. | Turbidostat |
Answer» B. Hemostat | |
365. |
Which of the following ROS is a powerful oxidizing agent? |
A. | Superoxide radical |
B. | Hydrogen peroxide |
C. | Hydroxyl radical |
D. | Singlet oxygen |
Answer» C. Hydroxyl radical | |
366. |
A bleb or fold like formation occurs in which of the following bacteria? |
A. | Rhodopseudomonas acidophila |
B. | Bacillus subtilis |
C. | E.coli |
D. | Streptococcus faecalis |
Answer» D. Streptococcus faecalis | |
367. |
The synthesis of new membrane material during reproduction in Gram-positive cells is performed by which of the following organelles? |
A. | Nucleus |
B. | Mesosome |
C. | Endoplasmic Reticulum |
D. | Cytoplasmic membrane |
Answer» C. Endoplasmic Reticulum | |
368. |
Equatorial ridge formation in the cell wall takes place in which of the following bacteria? |
A. | Streptomyces sp. |
B. | Bacillus subtilis |
C. | Streptococcus faecalis |
D. | Escherichia coli |
Answer» D. Escherichia coli | |
369. |
The Reactive Oxygen Species(ROS) poduced by some bacteria are degraded by which of the following enzymes? |
A. | Peroxidase |
B. | Lyase |
C. | Catalase |
D. | Superoxide dismutase, Catalase and Peroxidase |
Answer» E. | |
370. |
Transverse binary fission requires the formation of a crosswall. |
A. | True |
B. | False |
C. | May be |
D. | Can't say |
Answer» B. False | |
371. |
Bacteria having no flagella are unable to |
A. | move |
B. | reproduce |
C. | stick to tissue surfaces |
D. | grow in nutrient agar |
Answer» B. reproduce | |
372. |
The last step in synthesis of peptidoglycan is |
A. | attachment of a peptide to muramic acid |
B. | attaching two amino acids to form a cross-link |
C. | attachment of a portion of peptidoglycan to a membrane lipid |
D. | binding of penicillin to a membrane protein |
Answer» C. attachment of a portion of peptidoglycan to a membrane lipid | |
373. |
The bacterium Staphylococcus aureus is which type of bacteria? |
A. | Psychrophile |
B. | Mesophile |
C. | Thermophile |
D. | Mesophile and psychrophile |
Answer» C. Thermophile | |
374. |
Which is most likely to be exposed on the surface of a gram-negative bacterium? |
A. | Pore protein (porin) |
B. | Protein involved in energy generation |
C. | Lipoteichoic acid |
D. | Phospholipids |
Answer» B. Protein involved in energy generation | |
375. |
The cooci which mostly occur in single or pairs are |
A. | Streptococci |
B. | Diplococci |
C. | Tetracocci |
D. | None of these |
Answer» C. Tetracocci | |
376. |
A cluster of polar flagella is called |
A. | lophotrichous |
B. | amphitrichous |
C. | monotrichous |
D. | petritrichous |
Answer» B. amphitrichous | |
377. |
Which of the following are functions of phosphates used in the preparation of media? |
A. | they act as buffer |
B. | source of phosphorous |
C. | act as “reserve alkali” |
D. | they act as buffer and is a source of phosphorous |
Answer» E. | |
378. |
Which of the following is true about cell wall of gram-positive bacteria? |
A. | It consists of multiple layers |
B. | It is thicker than that associated with gram-negative bacteria |
C. | It contains teichoic acids |
D. | All of these |
Answer» E. | |
379. |
Which of the following are functions of Maintenance Media? |
A. | used for assay of vitamins,amino acids |
B. | used for determining the bacterial content |
C. | used for determining the type of growth produced by bacteria |
D. | used for the maintenance of the viability and physiological characteristics |
Answer» E. | |
380. |
The other name for peptidoglycan is |
A. | mucopeptide |
B. | murein |
C. | both (a) and (b) |
D. | none of these |
Answer» D. none of these | |
381. |
Circular, double-stranded and extrachromosomal DNA, can replicate independently of bacterial chromosome, called as |
A. | Plasmid |
B. | Cosmic |
C. | Vector |
D. | Template |
Answer» B. Cosmic | |
382. |
Colony formation can be observed in liquid media broth. |
A. | True |
B. | False |
C. | May be |
D. | Can't say |
Answer» C. May be | |
383. |
Which of the following bacteria requires nicotinic acid as a growth factor in their media? |
A. | Proteus vulgaris |
B. | Nitrosomonas sp. |
C. | E. coli |
D. | Leuconostoc mesenteroides |
Answer» B. Nitrosomonas sp. | |
384. |
The optimum pH for the growth of most bacteria lies between_______ |
A. | 5-9 |
B. | 6.5-7.5 |
C. | 2-3.5 |
D. | 9-9.5 |
Answer» C. 2-3.5 | |
385. |
Peptidoglycan is found only in the bacterial |
A. | cell membrane |
B. | glycocalyx |
C. | cell wall |
D. | spore |
Answer» D. spore | |
386. |
The endoflagella is present in which class of bacteria? |
A. | Spirilla |
B. | Spirochetes |
C. | Bacillus |
D. | Coccus |
Answer» C. Bacillus | |
387. |
Where is the endoflagella located in Spirochetes? |
A. | In the cell membrane |
B. | In the cytoplasm |
C. | In the peptidoglycan layer |
D. | In the periplasmic space |
Answer» E. | |
388. |
Spirochetes like other bacteria swim best in media of low viscosity. |
A. | True |
B. | False |
C. | May be |
D. | Can't say |
Answer» C. May be | |
389. |
Which of the following methods is used for viewing spirochetes? |
A. | Bright-field microscopy |
B. | Phase-contrast microscopy |
C. | Dark-field microscopy |
D. | Electron microscopy |
Answer» D. Electron microscopy | |
390. |
The family Leptospiraceae are aerobes. |
A. | True |
B. | False |
C. | May be |
D. | Can't say |
Answer» B. False | |
391. |
Which of the following bacteria lack a cell wall and are therefore resistant to penicillin? |
A. | Cyanobacteria |
B. | Mycoplasmas |
C. | Bdellovibrios |
D. | Spirochetes |
Answer» C. Bdellovibrios | |
392. |
Which of the following instrument is used for sterilizing the media after it has been prepared? |
A. | Autoclave |
B. | Laminar Air Flow Chamber |
C. | Inoculum Needle |
D. | Incubator |
Answer» B. Laminar Air Flow Chamber | |
393. |
Which of the following may contain fimbriae? |
A. | Gram-positive bacteria |
B. | Gram-negative bacteria |
C. | Both (a) and (b) |
D. | None of these |
Answer» C. Both (a) and (b) | |
394. |
Endotoxin is present in outer membrane of cell wall of gram-negative bacteria, known as |
A. | Polysaccharides |
B. | Lipopolysaccharides |
C. | Sugars |
D. | Lipid |
Answer» C. Sugars | |
395. |
Growth of bacteria or microorganisms refer to __________________ |
A. | an increase in the size of an individual organism |
B. | an increase in the mass of an individual organism |
C. | changes in the total population |
D. | an increase in number of cells |
Answer» E. | |
396. |
Cytoplasmic inclusions include |
A. | ribosomes |
B. | mesosomes |
C. | fat globules |
D. | all of these |
Answer» E. | |
397. |
Lag phase is also known as ___________ |
A. | period of initial adjustment |
B. | transitional period |
C. | generation time |
D. | period of rapid growth |
Answer» B. transitional period | |
398. |
Periplasm is |
A. | the area between the inner and outer membranes of gram-negative bacteria |
B. | the area between the inner and outer membranes of Gram-positive bacteria |
C. | the interior portion of mitochondria |
D. | the area outside the cell membrane that is influenced by the polymers |
Answer» B. the area between the inner and outer membranes of Gram-positive bacteria | |
399. |
Pleomorphic' is term used particularly for bacteria, havng |
A. | One shape |
B. | Rods |
C. | Spirals |
D. | Variable shape |
Answer» E. | |
400. |
Swimming towards a chemical of bacteria is termed as |
A. | positive chemotaxis |
B. | negative chemotaxis |
C. | phototaxis |
D. | magnetotaxis |
Answer» B. negative chemotaxis | |