Question

onion cells 10x, 40x cell wall, nucleus, cytoplasm rectangular, visible nucleus
starch grains 10x, 40x granules with hilum oval - shaped, concentric rings
plant fibers 10x, 40x fibrous strands elongated, thick cell walls
yeast cells 10x, 40x round cells, budding clustered, translucent
benzoic acid crystals 10x, 40x needle - like crystals transparent, sharp edges
aspirin crystals 10x, 40x plate - like or prismatic structures irregular, reflective
guide questions

1. why should you always start focusing with the low - power objective before switching to higher magnification?
2. what might happen if the coarse adjustment knob is used while viewing under high power?
3. why must both the slide and the cover slip be clean before observation?
4. compare the structures of biological specimens and crystalline organic compounds. what did you observe?
5. in microscopy, why is resolution sometimes more important than simply increasing magnification?
6. how is microscopy an essential skill for both biology and organic chemistry educators and researchers?

Explanation:

1. Starting with low - power objective allows for a wider field of view to locate the specimen easily. Higher magnification has a narrower field of view and it's harder to find the specimen.
2. Using the coarse adjustment knob under high power can cause the slide to be pushed too close to the objective lens, potentially damaging the slide or lens, and also causing the specimen to go out of focus rapidly.
3. Dirt or debris on the slide or cover slip can interfere with the light path, creating artifacts and obscuring the specimen, leading to inaccurate observations.
4. Biological specimens like cells have complex, living - related structures with organelles and specific shapes for their functions. Crystalline organic compounds have more regular, geometric shapes based on their molecular structures and crystal lattice arrangements.
5. Resolution is the ability to distinguish two closely - spaced objects. Just increasing magnification without sufficient resolution results in a blurry image. High resolution gives clear details even at lower magnifications.
6. In biology, microscopy helps in studying cells, tissues, and microorganisms. In organic chemistry, it can be used to study crystal structures of compounds, which helps in understanding their properties and reactions.

Answer:

1. To easily locate the specimen as low - power has a wider field of view.
2. May damage the slide or lens and cause rapid loss of focus.
3. To avoid artifacts and obscuring the specimen.
4. Biological specimens have living - related complex structures; crystalline organic compounds have more regular geometric shapes.
5. Because just increasing magnification without resolution gives a blurry image.
6. In biology for studying cells, tissues, etc.; in organic chemistry for studying crystal structures.