Ddt was a highly effective insecticide developed in the 1940s. ddt was so good at killing mosquitoes and reducing malaria that its inventor, paul muller, won the nobel prize. but in the 1960's it was discovered that ddt is taken up by algae in the water, increasing in concentration at each step of the food chain, because the pesticide remains in the fat tissues of organisms. the ecological problem that resulted from ddt use is called a) biohazard. b) bioremediation. c) biomagnification. d) food chain interruption.

If cells in the process of dividing are subjected to colchicines, a drug that interferes with the functioning of the spindle fibers, at which stage will mitosis be arrested?

You have been asked to lead a demonstration for the undergraduate microbiology lab course about the uses of negative staining when studying bacteria. a "negative" stain does not stain the bacterial cell itself but stains the space between cells. under magnification, the acidic (negativelycharged) nature of the stain will be repelled by the negatively charged bacterial cell wall and willleave the cell colorless in a stained background. negative stains are used primarily to reveal the presence of negatively charged bacterial capsules; therefore, they are also called capsule stains. encapsulated cells appear to have a halo surrounding them. the negative stain procedure does not require heat fixation, which limits any chances of alteration in bacterial cell shape and size. the bacterial suspension is added to a drop of stain, such as nigrosin or eosin, and drawn across the glass slide using a coverslip.nigrosin staining-not safranin staining-of klebsiella pneumoniae will allow for the visualization of the cell shape and the determination of the presence of a capsule.true/false

What is the period of cell life when it is conducting