⟩ What are biogeochemical cycles?
Biogeochemical cycles are representations of the circulation and recycling of matter in nature.
The main biogeochemical cycles studied in Ecology are the water cycle, the carbon cycle, and the nitrogen cycle.
Biogeochemical cycles are representations of the circulation and recycling of matter in nature.
The main biogeochemical cycles studied in Ecology are the water cycle, the carbon cycle, and the nitrogen cycle.
Which of the following statements is most correct about Atomic Force Microscopy (AFM)? A) AFM can visualize protein bound to DNA molecules. B) AFM can visualize unfixed specimens in water or buffer. C) AFM moves a very sharp tip over the surface of the specimen to "feel" its shape. D) All the statements above are true
Which of the following statements is most correct about the differential Gram stain? A) Crystal violet differentially stains Gram positive cells. B) Gram's iodine differentially stains Gram positive cells. C) Acetone differentially destains Gram negative cells. D) Saffron red differentially stains Gram negative cells
Which of the following objectives would give you the best resolution of small objects? A) 10x air, N.A. 0.25 B) 40x air, N.A. 0.65 C) 64x oil, N.A. 1.4 D) 100x oil, N.A. 1.25
Transmission electron microscopy is best for high magnification viewing of A) internal structure of fixed cells. B) internal structure of live, motile cells. C) surface structure of fixed cells. D) surface membranes of live, motile cells
Monochromatic (one color) light is sometimes used to increase the resolution of light microscopes. Light of which color below would give you the best resolution? A) Red B) Orange C) Green D) Blue
Scanning electron microscopy (SEM) is best used to study A) small internal cell structures. B) surface morphology. C) all of the above
Resolution is the ability of a lens to distinguish between small objects close together. What approximate resolution can be obtained with a lower power (10X, N.A. 0.25) objective lens? A) 0.2 microns B) 0.3 microns C) 0.9 microns D) 0.25
A microscope in which an image is formed by passing an electron beam through a specimen and focusing the scattered electrons with magnetic lenses is called a A) transmission electron microscope B) scanning electron microscope C) phase-contrast microscope
Living, unstained cells and organisms can be observed best using A) fluorescent microscopy B) TEM C) phase contrast microscopy
Fixation is the process by which the structures of the cells are preserved and fixed in position. An advantage of chemical fixation over heat fixation is that it A) magnifies the specimen B) does not destroy internal structures