Afamilial form of hypoparathyroidism is caused by a single point mutation in the gene encoding the preproparathyroid hormone. as a consequence of this point mutation, the signal sequence cannot be cleaved from the prepro-form of the mutant hormone. which statement below best describes the effect of this mutation upon synthesis of the preproparathyroid hormone? a) mrna encoding the mutant preproparathyroid hormone would accumulate in the nucleus and not be transcribed. b) the mutant preproparathyroid protein would not be targeted to the endoplasmic reticulum and thus would be translated by free ribosomes in the cytoplasm. c) the mutant preproparathyroid hormone would be incorrectly folded in the endoplasmic reticulum. d) the mutant preproparathyroid hormone would be inserted into the plasma membrane of the parathyroid cells. e) the mutant preproparathyroid hormone could not be stored in secretory vesicles, but instead would be secreted immediately following synthesis.

Scientist wanted to formulate a pool to attack a specific type of bacteria that infects with you. what biological component would be best to use as a model for the pills function?

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

In which situations is the principle of cross-cutting relationship useful in determining relative age?