Author: Anonymous

If you wished to decrease the rate at which a particle diffused from side A to side B of a phospholipid membrane, which of the following would be effective?

While working in a pharmacology lab, you develop a new compound that you think shows a lot of promise; however, you observe a concerning side effect: NADH now interacts with complex II instead of complex I. True or false: This change would lead to decreased efficiency of ATP production. 

The enzyme in the previous question allows the cell to continue the production of ATP by ________?

Spatial summation refers to which of the following? 

True or false: The Na+/K+ pump (ATPase) is a form of primary active transport.

Where can uracil be found?

Typical responses to ________ messengers require a long time to develop because they necessitate transcription of mRNA and translation of that mRNA into a functional protein.

True or false: The Golgi apparatus is involved in the process of synthesizing a peptide hormone to be secreted out of the cell.

Dual innervation of organs by the autonomic nervous system refers to the observation that ________.

Image Description  A graph depicting the changes in membrane potential during an action potential, illustrating various phases over time. The y-axis represents membrane potential in millivolts (mV), ranging from −90 mV to +70 mV, while the x-axis represents time in milliseconds (msec). Resting potential: The initial flat portion of the curve at −70 mV indicates the resting state of the membrane. This stage maintains the cell’s baseline electrical condition. Depolarization: The curve then rises from -70 mV, crossing a green dashed line labeled “Threshold potential” at approximately −55 mV. This upward slope signifies depolarization, where the membrane potential becomes less negative, indicating the beginning of an action potential. Peak of action potential: The curve peaks at approximately +30 mV, marked by a red label “Action potential”. This point represents the maximum depolarization, where the inside of the cell membrane is positively charged relative to the outside, crucial for transmitting nerve signals. Repolarization: Following the peak, the curve sharply declines back toward −55 mV. This downward slope indicates repolarization, where the membrane potential returns to a more negative value, restoring the initial conditions by expelling positive ions from the cell. Hyperpolarization: The curve dips below the original resting potential, reaching about −80 mV, before gradually returning to −70 mV. This phase is hyperpolarization, ensuring the cell does not immediately fire another action potential, providing a refractory period before stabilizing at the resting potential. The graph clearly illustrates the phases of an action potential: resting potential, depolarization, peak action potential, repolarization, and hyperpolarization. These stages are essential for the proper functioning of excitable cells like neurons and muscle cells.