How does sugar move through a plant?
1.Guard cells build up pressure, allowing dissolved sugars to enter the stomata.
2.Phloem in a sink region has lower pressure than in a source, so sugars flow out at the sink as water diffuses.
3.When the concentration of solute in the sieve tubes gets too low, osmosis allows water to flow in.
4.The pressure gradient allows dissolved sugars to reach high levels in the xylem, pushing them to a sink where they are released.
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Evaluate the following statements. Which one is most accurate?
A. Since bacteria reproduce asexually, all bacteria originating from one source are genetically identical to each other. B. While bacteria reproduce asexually, they use many mechanisms to transfer genetic materials between each other and as such as not all genetically identical to each other. C. Bacteria reproduce sexually, and have many mechanisms to spread their genetic materials to other bacteria. D. Bacteria reproduce asexually, and as such do not have mechanisms to generate genetic diversity among themselves.
Fine structure genetic maps of the human genome are now constructed using either restriction fragment length polymorphisms (RFLPs) which are found about 1/6000 bp
or single nucleotide polymorphisms (SNPs) which are found about 1/1330 bp. Would you expect RFLPs or SNPs to be located only in the coding regions of genes or in noncoding and repetitive sequences as well? What will be an ideal response?
Scrubbing or immersing the skin in chemicals to reduce the numbers of microbes on the skin is
A. degermation. B. sanitization. C. sterilization. D. disinfection.
Transcription takes place in the ____of the cell
Fill in the blank(s) with the appropriate word(s).