How Can Plant Diseases Reduce The Yield Of Crops

Question: How can plant diseases reduce the yield of crops?

a) By making the crop inedible

b) By attracting predators

c) By reducing the photosynthetic areas on leaves

d) By reducing temperature around the leaves

Answer: c) By reducing the photosynthetic areas on leaves

Question:

Answer: c) Fungus

Question:

Answer: c) There is a pinhole to filter out unfocused light

Question: Which of the following is NOT an advantage of using confocal microscopy over widefield microscopy?

a) It can be used to produce a 3D image

b) The depth of imaging can be controlled

c) The image resolution is greater

d) It’s cheaper than conventional light microscopy methods

Answer: d) It’s cheaper than conventional light microscopy methods

Question:

Answer: d) They are chemical compounds that re-emit light of a longer wavelength after exposure

Question: In confocal microscopy, what risk do lasers pose to the user?

a) The lasers can potentially burn the skin

b) Extremely high risk

c) They pose no risk at all

d) Exposure to the lasers is hazardous for the eyes

Answer: d) Exposure to the lasers is hazardous for the eyes

Question: Why is a laser used in confocal microscopy?

a) Laser beams are highly divergent

b) They have a lower energy consumption than other light sources

c) They are cheaper and easier to use than other light sources

d) Laser beams are highly monochromatic

Answer: d) Laser beams are highly monochromatic

Question: Why is a photomultiplier tube (PMT) needed as the detector?

A)To increase the fluorescent signal

b) To reduce the background signal

c) To connect the microscope to the computer

d) To increase the resolution

Answer: To increase the fluorescent signal

Question:

Answer: c) Because the beam is scanned across the sample using a mirror

Question: What happens when the gain is too high?

a) The signal-to-noise ratio detected by the PMTS increases

b) The sample becomes.overexposed, and you get a high definition image

c) The lasers may become damaged over time

d) The sample becomes overexposed and may photobleach

Answer: d) The sample becomes overexposed and may photobleach