In some areas of the world where there are large numbers of pine trees, in the spring everything is covered with a yellow dust that turns out to be pine pollen
Why must conifers produce so much pollen, and why doesn't a field of flowers produce so much pollen?
Pines are pollinated by the wind, so they must produce large excesses of pollen. Field flowers are pollinated by insects and therefore don't have to produce so much pollen.
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During a microarray analysis, cDNAs made from normal cells are stained with a green fluor and cDNAs from
abnormal cells are stained with a red fluor. Which of the following statements is true about the results of this experiment?
a. Red spots indicate genes that are under expressed in abnormal cells. b. Red spots indicate genes that are not expressed in abnormal cells. c. Red spots indicate genes that are overexpressed in abnormal cells. d. Red spots indicate genes that are overexpressed in normal cells. e. Red spots indicate pseudogenes.
Which of the following traits is characteristic of a K-selected species?
a. adapted to rapidly changing environments b. small body size c. short generation time d. provide substantial parental care to offspring e. single reproductive event common
Which of the below is a hallmark of cancer?
a. generate their own mitogenic signals b. resist exogenous growth-inhibitory signals c. evade apoptosis d. all the above are hallmarks of cancer
When a polypeptide is being assembled, the bond that forms between a newly added amino acid and the previous amino acid in the chain is this type of bond.
A. hydrophobic B. peptide C. phosphodiester D. hydrogen E. terminal