Cell Biology - Questions and Answers for Competitive Exams | GkSeries

25. The total magnification of a microscope with the low power lens (10X) and ocular lens (15X) in position would be _________

• [A] 25
• [B] 15
• [C] 150
• [D] 1500

Answer: Option [C]

26. Heat fixation accomplishes all the following expect ________.

• [A] helps the dye to penetrate the cells
• [B] kills the bacteria on the slide
• [C] decreases distortion of the cells prior to the addition of strains
• [D] fixes the organisms to the slid

Answer: Option [C]

27. If a bacterium measures 0.3 micrometer, it would measure how many angstroms?

• [A] 300
• [B] 30
• [C] 3000
• [D] 3

Answer: Option [C]

28. Which of the following would not be consistent with eukaryotic organisms?

• [A] membrane bound organelle
• [B] presence of histones
• [C] cell membranes lacking sterols
• [D] paired chromosomes

Answer: Option [B]

29. Which of the following methods is NOT used to determine bacterial numbers?

• [A] turbidity
• [B] serial dilution
• [C] direct microscopic counts
• [D] all the above

Answer: Option [D]

30. Endospores ________

• [A] are generally formed for protection and reproduction
• [B] are formed only when conditions become unfavorable.
• [C] contain dipicolinic acid and calcium
• [D] contain laminated layers of peptidoglycan called the exosporium

Answer: Option [C]

31. A specially calibrated counting chamber used with direct microscopic counts is called _________.

• [A] petroff hausser counter
• [B] haemocytometer counter
• [C] Geiger-Muller counter
• [D] Geiger-Müller photoelectron counter

Answer: Option [A]

32. The ratio of diameter of lenses to its focal length is referred as ________.

• [A] magnification
• [B] resolution
• [C] numerical aperture
• [D] focal length

Answer: Option [A]

33. Use of single stain to color the bacteria is commonly called as ________ staining

• [A] simple
• [B] Gram
• [C] differential
• [D] negative

Answer: Option [A]

34. A preserved culture maintained to keep its characteristics as originally defined is a _______

• [A] reference culture
• [B] standard culture
• [C] enrichment culture
• [D] selective culture

Answer: Option [A]

35. Pasteur is credited with all the following except ________.

• [A] construction of swan necked vessels
• [B] development of a vaccine for rabies
• [C] development of the technique for rabies
• [D] became the director of the Pasteur institute in Paris, France

Answer: Option [D]

36. One of the most important contributions of Robert Koch in his development of the germ theory of disease was the ________.

• [A] use of test animals in research
• [B] use of the microscope
• [C] development of the technique of pure culturing
• [D] development of the busen burner

Answer: Option [C]