NURSING EXAM QUESTIONS
BIOCHEMISTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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0.1 µm to 10 µm.
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0.3 µm to 30 µm.
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0.3 µm to 100 µm.
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1 µm to 100 µm.
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1 µm to 300 µm.
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Detailed explanation-1: -The dimensions of living cells are limited, on the lower end by the minimum number of biomolecules necessary for function, and on the upper end by the rate of diffusion of solutes such as oxygen. Except for highly elongated cells, they usually have lengths and diameters in the range of: 0.3 m to 100 m.
Detailed explanation-2: -Diffusion is effective over a specific distance and limits the size that an individual cell can attain. If a cell is a single-celled microorganism, such as an amoeba, it can satisfy all of its nutrient and waste needs through diffusion.
Detailed explanation-3: -How does cell size and shape influence diffusion into and out of the cell? As cell size increases, its ability to facilitate diffusion across the cell membrane decreases. This is because its internal volume increases at a faster rate than its external surface area.
Detailed explanation-4: -At 0.1 to 5.0 m in diameter, prokaryotic cells are significantly smaller than eukaryotic cells, which have diameters ranging from 10 to 100 m.
Detailed explanation-5: -Out of the three shapes found in epithelial tissues (squamous, cuboidal, and columnar), the best at allowing for simple diffusion is squamous. This is why these types of cells are found in alveolar tissue.