Answer:In old stems the epidermal layer, cortex, and primary phloem become separated from the inner tissues by thicker formations of cork. Due to the thickening cork layer these cells die because they do not receive water and nutrients. This dead layer is the rough corky bark that forms around tree trunks and other stems.
Explanation: wikipedia.
I don’t know the answer to this question
Answer:
The correct answer is - Yes, the genetic engineer should create a genomic library or a cDNA library.
Explanation:
mRNA isolated from the toxin extracted from the venom gland of the scorpion to create a cDNA library. The cDNA sequence is reverse transcribed by the mRNA that lacks the introns as prokaryotic organisms such as bacteria cannot splice introns.
If the engineer wants to express the toxin in bacteria then he required a cDNA sequence as a genomic clone can not use to clone for making proteins. mRNA should be isolated from the venom gland so it can synthesize cDNA library enriched with toxin protein sequence.
Isotonic solution.
Since it has the same salt concentration as the cell the solution is neither hypotonic or hypertonic.
#19 due to weathering and erosion the rock from the stream was smoothened and without as much the rock from deep underground was/is very rugged and natural.
#18 Due to wind patterns the sand dunes are blew around and the sands shift and fly around with nothing to keep the sand in place the sand can go long distances or come long distances.
(I am back lol)