Q: While the numerical aperture can be used to compare resolutions of various objectives, it does not indicate how far the lens could be from the what? Read this paragraph and choose the correct option from the provided answers: While the numerical aperture can be used to compare resolutions of various objectives, it does not indicate how far the lens could be from the specimen. This is specified by the "working distance," which is the distance (in mm usually) from the front lens element of the objective to the specimen, or cover glass. The higher the NA the closer the lens will be to the specimen and the more chances there are of breaking the cover slip and damaging both the specimen and the lens. The focal length of an objective lens is different than the working distance. This is because objective lenses are made of a combination of lenses and the focal length is measured from inside the barrel. The working distance is a parameter that microscopists can use more readily as it is measured from the outermost lens. The working distance decreases as the NA and magnification both increase. Choices: - microscope - diameter - focal point - specimen A:
specimen
------
Q: Changing the shape of an elastic material gives it what type of energy? Read this paragraph and choose the correct option from the provided answers: Changing the shape of an elastic material gives it potential energy. Choices: - thermal - practical - initial - potential A:
potential
------
Q: After dispersal of a seed, what next step may occur if environmental conditions are favorable? Read this paragraph and choose the correct option from the provided answers: Choices: - bloom - degradation - infection - germination A:
germination
------
Q: Categorized based on how they produce their mrna using the baltimore classification method, what consist of a nucleic acid core surrounded by a protein capsid with or without an outer lipid envelope? Read this paragraph and choose the correct option from the provided answers: CHAPTER SUMMARY 21.1 Viral Evolution, Morphology, and Classification Viruses are tiny, acellular entities that can usually only be seen with an electron microscope. Their genomes contain either DNA or RNAnever bothand they replicate using the replication proteins of a host cell. Viruses are diverse, infecting archaea, bacteria, fungi, plants, and animals. Viruses consist of a nucleic acid core surrounded by a protein capsid with or without an outer lipid envelope. The capsid shape, presence of an envelope, and core composition dictate some elements of the classification of viruses. The most commonly used classification method, the Baltimore classification, categorizes viruses based on how they produce their mRNA. Choices: - bacteria - amphibians - parasites - viruses A:
viruses
------