The heart pumps harder and blood pressure rises during a fight-or-flight response. this response is due to
a. thyroxine secreted by the thyroid gland.
b. adrenaline secreted by the adrenal glands.
c. insulin secreted by the pancreas.
d. oxytocin secreted by the pituitary gland.

Which of the following is most important in making the typical seed more resistant to adverse conditions than the typical spore? a) a different type of sporopollenin b) an internal reservoir of liquid water c) integument(s) d) ability to be dispersed e) waxy cuticle

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

Number and variety of living organism; includes genetic, species, and ecological types