13. which of the following is not required by animals to control body temperature? a. animals must switch between ectotherm and endotherm methods. b. animals must be able to get rid of excess heat when temperatures increase. c. animals must be able to conserve heat when temperatures drop. d. animals must find a source of heat.

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

Some mining processes involve removal of large areas of earths surface in the mined region this practice causes severe environmental damage by allowing which natural process to accelerate in the affected areas? a. precipitation b. erosion c. migration d. condensation

What is the statement plant growth is affected by the color light