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Biol 320 Exam 3 Newest 2025 Actual Exam Complete Questions And Correct Answers(Verified Answers) |Already Graded A+
The sodium potassium pump is an example of a protein that has several different domains. One specialized region of the protein is responsible for breaking the bond between a phosphate group and adenosine triphosphate, ultimately attaching that phosphate to an amino acid side chain found within itself.What would be an appropriate name for this domain of the sodium potassium pump?sodium binding domain potassium binding domain phosphorylation domain voltage sensing domain - ANSWER-phosphorylation domain
Which of the following explains why Ouabain, a chemical derived from a plant found in some regions of the world, is capable of killing a massive mammal like a hippo?the molecule leads to an increase in extracellular sodium 1 / 4
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the molecule prevents heart muscle cells from maintaining the sodium gradient ouabain directly blocks the coupled pump for calcium ouabain prevents facilitated diffusion of sodium up its gradient - ANSWER-the molecule prevents heart muscle cells from maintaining the sodium gradient
Ion channels have different gating mechanisms. Which of the following is NOT an example of how these mechanisms work?voltage gated ion channels open in response to a change in water distribution across the membrane a mechanically gated potassium channel opens in response to physical stimulus ligand gated ion channels require the binding of a molecule that causes a conformation shift in the channel protein voltage gated ion channels can be affected by the concentration gradients of positive or negatively charged ions - ANSWER- voltage gated ion channels open in response to a change in water distribution across the membrane
As long as a channel is open, it will allow selective diffusion of a particular solute DOWN its gradient.True 2 / 4
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False - ANSWER-true
Most proteins that transport hydrophilic molecules across the membrane contain one alpha helix that crosses the plasma membrane a single time.True False - ANSWER-false
Phosphorylation of the Na+-K+ pump is performed by a kinase that diffuses through the cytosol of a cell.True False - ANSWER-false
The direction that glucose is transported across the membrane is
determined by:
The concentration gradient The membrane potential The molecule's charge The molecule's size - ANSWER-The concentration gradient
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Which of the following are differences between channels and transporters?Only transporters are selective in which solutes they transport Transporters are only used for active transport, while channels are only used for facilitated diffusion.Only transporters change shape each time a solute is moved Only transporters are regulated by ligands and voltage changes - ANSWER-Only transporters change shape each time a solute is moved
Channels use the energy from ATP hydrolysis to move ions UP (against) their electrochemical gradient.True False - ANSWER-false
The energy for secondary active transport is supplied by ATP phosphorylation of the coupled transporter An ATP hydrolysis reaction performed by the coupled transporter An electrochemical gradient of another ion Moving glucose from high to low concentration - ANSWER-An electrochemical gradient of another ion
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