Norepinephrine (NE) Can Bind to the β-Adrenergic Receptor and Speed

question 51

Essay

Norepinephrine (NE) can bind to the β-adrenergic receptor and speed up heart rate through the cAMP signaling cascade. The cAMP cascade results in the phosphorylation of a voltage-gated Ca²⁺ channel, which increases its open probability. For each situation below state if the Ca²⁺ channel open probability increases, decreases, or does not change.
A. Intracellular addition of cAMP, in the absence of application of NE
B. In the absence of NE application, the inability of GTP to dissociate from Gα
C. In the presence of NE application, the inability of GDP to dissociate from Gα

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Definitions:

Number

A mathematical object used to count, measure, and label.

Chi-Squared Distribution

A probability distribution widely used in inferential statistics for hypothesis testing and in constructing confidence intervals, especially useful for categorical data.

Degrees of Freedom

The number of independent pieces of information available to estimate another piece of information or the parameters in a statistical model.

Mean

The average value of a set of numbers, obtained by dividing the sum of all the numbers by the count of numbers.