When adrenaline binds to adrenergic receptors on the surface of a muscle cell, it activates a G protein, initiating an intracellular signaling pathway in which the activated ? subunit activates adenylyl cyclase, thereby increasing cAMP levels in the
cell. The cAMP molecules then activate a cAMP-dependent kinase (PKA) that, in turn, activates enzymes that result in the breakdown of muscle glycogen, thus lowering glycogen levels. You obtain muscle cells that are defective in various components of the signaling pathway. Referring to Figure Q16-36, indicate how glycogen levels would be affected in the presence of adrenaline in the following cells. Would they be higher or lower than in normal cells treated with adrenaline?
A. cells that lack adenylyl cyclase
B. cells that lack the GPCR
C. cells that lack cAMP phosphodiesterase
D. cells that have an ? subunit that cannot hydrolyze GTP but can interact properly with the ? and ? subunits
A. higher
B. higher
C. lower
D. lower
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Crosses between a yellow rat with a yellow rat always produce yellow offspring. Crosses between a white rat with a
white rat always produce white offspring. The alleles affect the same aspect of coat color. The cross of a white rat with a yellow rat produces a cream rat. If you cross two cream rats, what will be the ratios of phenotypes of the offspring? What will be an ideal response?
The tectorial and basilar membranes are located
within a. A. b. B. c. C. d. E. e. another unlabeled region of this figure.
Which of the following statements with respect to oxytocin and vasopressin is false?
A) They are secreted in response to hypothalamic releasing hormones B) They are peptide hormones C) They are posterior pituitary hormones D) They are synthesized in cell bodies of the hypothalamus
Which proteins function in the resolution of Holliday junctions?
a. the Ruv complex b. integrases c. Zip proteins d. the RecBCD complex e. cohesins