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Pavlova-9 [17]
3 years ago
9

Individual cells are usually very small because...?

Biology
2 answers:
sveta [45]3 years ago
7 0
They are usually small because they need to transport nutrients across the membrane. Only particular amount can cross per/area. As the volume of cell increases, it increases in geomatrically faster than the area of the membrane.It becomes difficult to a certain point to supply the given volume with enough membrane to allow the gases/other molecules to transport across the membrane

:)
Rama09 [41]3 years ago
4 0
Because the people that mae them wanted them to be very small

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What if xylem were only located in the roots and stems, would fluids still move? No because xylem have stoma that enables transpiration to happen. If you remove xylem, you've removed that "vacuum" that pulls that water upward

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Biochemical and differential tests can be incorporated into growth media or performed on isolated colonies after they have been
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<h2>Differential test</h2>

Explanation:

A differential test helps to distinguish that which species lack or have the particular biochemical process,the three differential test media are:

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  • It is also required to detect and differentiate haemolytic bacteria, especially Streptococcus species
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2) Eosin methylene blue agar (EMB): It is a selective and differential medium used to isolate fecal coliforms

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Three examples of tests which are done on colonies are:

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  • Incubation is done at 35°C (+/- 2°C) for 24 to 48 hours
  • To test for indole production, 5 drops of Kovács reagent is directly added to  the tube
  • A positive indole test is indicated by the formation of a pink to red color  in the reagent layer on top of the medium within  seconds of adding the reagent
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3) Urease test: Urease is a constitutively expressed enzyme that hydrolyzes urea to carbon dioxide and ammonia

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The answer is D My lovely

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