1. In an electron microscope, higher magnification is due to the use of
Higher wavelengths of Light
High velocity electrons
Achromatic lenses
Magnetic system
(b) High magnification of electron microscope is due to Electron beam, Electromagnets, High voltage. Correct option is D) Electron microscopes differ from light microscopes in that they produce an image of a specimen by using a beam of electrons rather than a beam of light. Electrons have much a shorter wavelength than visible light, and this allows electron microscopes to produce higher-resolution images than standard light microscopes. Hence the correct answer is (D)
2. Which of the following is related to genetic engineering?
Plastids
Plasmids
Mutations
Hybrid vigour
(b)
3. A student wants to study metaphasic behaviour chromosomes. The technique most suitable is
Phase contrast microscope
X-ray microscope
Cell fractionation
Scanning electron microscope
(a)
4. Magnification of a compound microscope does not depend upon
Focal length of objective
Focal length of eyepiece
Tube length of microscope
Numerical aperture of objective
(d) In compound microscope, magnification does not depend upon Focal length of lens, Numerical aperture of objective lens, Tube length of microscope, All of the above. The numerical aperture of a microscope objective lens is a measure of its ability to accept light and resolve fine specimen detail at a fixed object distance. It is the important parameter to any optic fibers. It determines the resolving power of the objective. The higher the NA of the total system, the better the resolution. The magnification does not depend on numerical aperture. Thus, the correct answer is option B.
5. Dark field microscopy is used to detect bacteria. It makes use of
Invisible far light
Invisible UV light
Visible light
Does not use any light
(c)
6. Pure fractions of cellular components can be obtained by
X-ray diffraction
Chromatography
Differential centrifugation
Microspectrophotometry
(c)
7. Biomembrane appears to be trilaminar or tripartite under
Light microscope
Electron microscope
Phase-contrast microscope
Fluorescent microscope
(b)
8. To study the physiological function of a cell organelle, the method used is
Autoradiography
Fractionation
Electron microscope
None
(b) Have you ever wondered how scientists were able to determine that mitochondria are the powerhouses of the cell or how they figured out that the endoplasmic reticulum has a different function from the Golgi apparatus? Scientists were able to discern the functions of organelles by separating them in a process called cell fractionation.
The process is pretty simple; you take some cells, throw them in a blender, and then centrifuge them to separate the organelles, as shown in this figure.
9. Feulgen reaction, a technique developed by Feulgen and Rossenbeck to study or to stain (or a Feulgen reaction is a specific test for establishing the presence of
DNA
RNA
Protein
Lipids
(a)
10. Which microscope would you require if asked to examine a culture of unstained living and dividing cells?
Scanning electron microscope
Transmission electron microscope
Phase contrast microscope
Polarization microscope
(c)
11. The technique used for estimation of minor amounts of hormones and drugs is called
Electrophoresis
Electroencephalogram
Fractionation
Radioimmunoassay
(d)
12. Vital stains are employed in the study of
Living cells
Dead cells
Both (a) and (b)
None of these
(a)
13. Dye used in Feulgen's test for detection of DNA is
Janus green
Basic fuchsine
Methylene blue
Acetocarmine
(b)
14. If the dicot stem is stained for starch. The most intense colouration would develop in
Epiblema
Phloem
Endodermis
Pith
(c) Epiblema is the outer layer of the roots also known as epidermal cells of roots which perform the function of absorption.
Phloem is the conducting strands or tissues for the transport of food and minerals and is thus responsible for the nutrient supply of plants.
Endodermis is the layer in the center that surrounds the cortex of roots and stems. it is the layer which surrounds the vascular bundles. It is also called a starch sheath which has starch grains in the stems of dicots.
Pith is the central part of roots and stems which help in the nutrients supply.
So, the correct option is 'Endodermis'.
15. The process through which the amount of DNA, RNA and protein can be known at a time is called
Autoradiography
Tissue culture
Cellular fractioning
Phase contrast microscopy
(a) Correct option is A)
Tissue culture refers to the aseptic culture of cells/tissues/organs or their parts under in vitro conditions.
Cellular fractionation techniques refer to the separation of all cellular organelles through sequential homogenization, filtration, and purification methods.
The phase-contrast microscopy takes advantage ability of different cell parts to alter the light passing through them in a subtle way according to their respective density to distinguish different cellular components.
Autoradiography includes labeling of biomolecules with radioactive material (radioactive thymine for DNA, radioactive uracil for RNA, and radioactive S for proteins) followed by localizing these radioactively labelled molecules by applying photosensitive emulsion on the surface of prepared slides.
Thus, the correct answer is option A.
16. Dye which cannot stain chromatin is
Crystal violet
Fuelgen stain
Haematoxylin
Acetocarmine
(b)
17. Electron microscope has revealed the occurrence of
Leucoplasts
Chloroplasts
Chromosomes
Ribosomes
(d)
18. A living cell can be studied by means of
Dark field microscope
Electron microscope
Phase - Contrast microscope
Compound microscope
(c)
19. Intact chloroplast of green cells can be isolated with the help of
Alcohol
Acetone
Carbon disulphide
Sugar solution
(d) Intact chloroplasts of green cells can be isolated with the help of i. Acetone ii. Alcohol iii. Carbon disulphide iv. 0.5 M solution of sucrose Correct option is D) Chloroplast can be isolated in tris-HCl buffer made 0.5M with respect to the sucrose. Here, the extracts of the chloroplast extracted with the sucrose solution had considerable enzymatic activity and did not inhibit this activity. Thus, the correct answer is option (D), '0.5 M solution of sucrose'.
20. To determine the ultra structure of a cell organelle, the most likely method to be used would be
Electron microscopy
Microdissection
Autoradiography
Phase contrast microscopy
(a)
21. Organelles can be separated from cell homogenate through
Chromatography
X-ray diffraction
Autoradiography
Differential centrifugation
(d)
22. The most significant drawback in electron microscope is that
It is very costly
It requires high technical skill
It is to be lodged in vacuum
Living cells can't be observed under it
(d)
23. Which rays are used for making image for CT scan?
X-rays
Positron emitting from radiographs
Hydrogen ions
Ultrasound waves
(a) A CT scan, or computed tomography scan, sends radiation through the body. However, unlike a simple X-ray study, it offers a much higher level of detail, creating computerized, 360-degree views of the body's structures. CT scans are fast and detailed. They take longer than X-rays but are still fast (about one minute).
24. Iodine solution is used to test the presence of
Carbohydrates
Proteins
Fats
Starch
(d)
25. The technique used for separating DNA fragments is
Southern blotting
Northern blotting
Western blotting
Eastern blotting
(a)
26. Fluidity of bio-membranes can be shown by
Electron microscope
Tissue culture
Phase-contrast microscope
Fluorescent microscope
(d) Correct option is D)
In biology, membrane fluidity refers to the viscosity of the lipid bilayer of a cell membrane or a synthetic lipid membrane.
Laurdan was first applied to study membrane fluidity of live cells with a 2-Photon fluorescence microscope in 1994. A fluorescence microscope is an optical microscope that uses fluorescence and phosphorescence instead of, or in addition to, reflection and absorption to study properties of organic or inorganic substances.It is used to investigate membrane qualities of the phospholipid bilayers of the cell. Hence, option D is correct.
27. DNA synthesis can be measured by estimating incorporation of radio-labelled
Uracil
Ribose sugar
Thymidine
Adenine
(c)
28. Binding of specific protein on regulatory DNA sequences can be best studied by means of
Ultra centrifugation
Electron microscope
Light microscope
X-ray crystallography
(d)
29. Angstrom (A) is equal to
0.0001 um
10-10 m
0.1 nm
All of the above
(d)
30. The unit for measuring size of the cell is
nm
mm
Å
μm
(d)
31. The technique of obtaining large number of plantlets by tissue culture method is called
Organ culture
Plantlet culture
Macropropagation
Micropropagation
(d)
32. The maximum magnification produced by light microscope is about
50 times
100 times
1000 times
2000 times
(c)
33. Cell organelles can be physically separated of each other by
Microscopy
Centrifugation
Chromatography
Radioactive tracers
(b)
34. The first protein whose structure was determined by X-ray diffraction
Myoglobin
Insulin
Haemoglobin
Collagen
(a) X-ray crystallography was first used to determine protein structure in the late 1950s. John Kendrew and Max Perutz while both at Cambridge used x-ray crystallography to discover the structure of hemoglobin & myoglobin(oxygen carrier in muscle) in 1945. They received the Nobel Prize in chemistry in 1962. What was the first protein structure determined? myoglobin Muscle's myoglobin, the first protein structure revealed: After 22 years of work, John Kendrew of the Cavendish Laboratory in Cambridge (UK) uses X-ray diffraction to determine the 3-dimensional structure of myoglobin, the first protein to have its structure determined.
35. Feulgen reaction is
Positive in both nucleus and cytoplasm
Negative in both nucleus and cytoplasm
Positive in nucleus and negative in cytoplasm
Positive in cytoplasm and negative in nucleus
(c)
36. The technique used for estimation of minimum amount of hormones and drugs is called
Fractionation
Electrophoresis
Radioimmunoassay
Electroencephalogram
(c)
37. Radioactive isotope P32 has been used experiment, carried out by
Hammerling
Hershay and Chase
Watson and Crick
Nirenberg
(b) To prove that DNA is the genetic material, which radioactive isotopes were used by Hershey and Chase(1952) in their experiments? 35S and 15N 32P and 35S 32P and 15N 14N and 5N Correct option is B) Hershey and Chase experiment is based on the fact that DNA contains phosphorus and similarly, sulphur is present in proteins but not in DNA. They incorporated radioactive isotope of phosphorus (32P) into phage DNA and that of sulphur (35S) into proteins of a separate phage culture. Viruses grown in the presence of radioactive phosphorus contained radioactive DNA but not radioactive protein because DNA contains phosphorus but proteins do not, Similarly, viruses grown on radioactive sulphur contain radioactive- protein but not-radioactive DNA because DNA does not contain sulphur. So, the correct answer is '32P and 35S'.
38. If the cells are broken up and sedimented by centrifugation the new structure formed in one of fraction is
Ribosome
Lysosome
Spherosome
Microsome
(d)
39. Mitochondria was discovered with the help of
Compound microscope
Electron microscope
Scanning electron microscope
Autoradiography
(a)
40. Transmission electron microscope has high resolution of
0.2 nm
2nm
200 nm
2000 nm
(a)
41. Phenology concerns with
Physiology
Anatomy
Periodical phenomena
Paleobotany
(c)
42. Middle lamella can be stained with
Light green
Iodine
Methylene blue
Cotton blue
(d)
43. Autoradiography technique was used to study
Absorption spectra of photosynthesis
Peroxisome
Light reaction
Calvin cycle
(d) The Calvin cycle was discovered by Calvin, Benson and their colleagues in California, U.S.A. They fed Chlorella and Scenedesmus with radioactive 14C in carbon dioxide. Radioactive carbon, 14C has a half-life of 5568 years. Therefore, the path of CO2 fixation during photosynthesis can be easily traced with its help.
44. The quantitative analysis of a substance can be made with the help of
X-ray crystallography
Spectrophotometry
Autoradiography
Calorimetry
(b) A spectrophotometer is an instrument that measures the amount of photons (the intensity of light) absorbed after it passes through sample solution. With the spectrophotometer, the amount of a known chemical substance (concentrations) can also be determined by measuring the intensity of light detected.
45. The resolution power of light microscope is
0.1 μm
0.2 μm
0.3 μm
0.4 μm
(b)
46. In the experiment of Melson and Stahl to demonstrate semiconservative mode of DNA replication, the radio-isotope used was
N15
P32
H3
None
(a)
47. Electron microscope works on the principle of
Particle nature of electron
Wave nature of electron
Both
None
(c)
48. The first operational microscope was produced by
Robert Hooke
A.V. Leeuwenhook
N. Grew
Janssens
(d)
49. The smallest size of cell visible to naked eye
10μ
100μ
1000μ
None
(b)
50. How many angstroms make a metre
109
1010
103
106
(b)
51. Electron microscope was invented by: [BPKIHS - 2014]
[BPKIHS - 2014]
Knoll and Ruska
Robert Hooke
Janssen and Janseen
Knoll and Hooke
(a)
52. In electron microscopy, ultra - thin specimens are impregnated with [BPKIHS - 2014]
