Please answer The figure below shows the structure of a porin subunit embedded in the lipid bilayer (left: sideview, right: top view). Hydrophobic residues are shown as yellow sticks, polar residues are shownas green sticks, negatively charged residues are shown as red sticks, and positively chargedresidues are shown as blue sticks. Porins form open water-filled channels that passively diffusesnutrients and waste products across the membrane.sFrom its structure, discuss physical properties of molecules that can pass through the porin. Also,discuss how its structure relates to its function. Identify the secondary structure/s present in theprotein.

A transmembrane protein is a protein that traverses through the membrane entirely from one side to…

Answered: The figure below shows the structure of…

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter2: Cell Physiology

Section: Chapter Questions

Problem 11RE

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Similar questions

Liposomes have long been investigated as drug delivery mechanisms in humans and animals, but only recently have they started to be used clinically in targeted cancer therapies and now, vaccines. Liposomes are simply vesicles with a phospholipid bilayer that contain an inner aqueous compartment. Hydrophilic compounds could be carried in the buffer inside the liposome or hydrophobic drugs within the membrane itself. For instance, the Moderna and Pfizer mRNA vaccines actually use liposome technology to deliver the SARS-CoV-2 spike mRNA to human cells. The liposomes fuse with the plasma membrane allowing the contents of the liposome to enter the cytosol of cells. Of course, once the mRNA is in the cytosol is can be translated to protein on a ribosome. Explain why nucleic acid won’t get through the plasma membrane on its own. Discuss the energetic restrictions to movement through the membrane
In the "fluid " _______ cell membrane model, lipids are organized in a ________ arrangement, such that _______ portions of the lipids are exposed to either the interior or exterior of the cell, while the lipid portions are sandwiched in the middle of the membrane. As part of the cell membrane, a main function of peripheral proteins is to provide _________ , while a main function of proteins is to provide _________ . Other cell membrane molecules include a compound called __________, which functions to provide fluidity to rigid membranes and rigidity to fluid membranes; and surface carbohydrates, which function in the membrane not to provide energy, but instead to provide _________ _____ . Aminophospholipids (including PE and ) move to the inner leaflet of the membrane, by an enzyme known as the ._______ A main function of the cell membrane is to be very selective as to what is able to cross through, a condition known as a barrier.
Which of the following is not a lipid link that anchors membrane-associated proteins to the bilayer? Thioether-linked prenyl anchors. Ester-linked triacylglycerol anchors. Glycosyl phosphatidylinositol anchors. Thioester-linked fatty acyl anchors. Amide-linked myristoyl anchors.
Which of the following is true about motion of membrane lipids? A. They can move most rapidly when in the gel phase. B. Lateral diffusion is catalyzed by flippase proteins. C. To increase the fluidity of membranes at low temperatures, cells synthesize more saturated fatty acids and fewer unsaturated fatty acids. D. Transbilayer diffusion involves the transfer of lipids from one face of the bilayer to another.
Biological membranes are critical components of cells that allow compartmentalisation of cellular contents. The diagram shows a biological membrane comprised of a lipid bilayer with a single polypeptide integrated into the membrane and spanning the membrane seven times. What is the name of the specific type of lipid comprising the bilayer shown above? What properties about the heads and tails of these lipid structures force them to be arranged as they are in the lipid bilayer?
Which of the following statements are acceptable and why? [Whereas all the carbohydrate in the plasma membrane faces outward on the external surface of the cell, all the carbohydrate on internal membranes faces toward the cytosol.] [Although lipid molecules are free to diffuse in the plane of the bilayer, they cannot flip-flop across the bilayer unless enzyme catalysts called phospholipid translocators are present in the membrane.]
Draw and label a cell lipid bilayer and diagram how the following transport processes take place: passive diffusion of oxygen into the cell, facilitated diffusion of potassium into the cell, active transport of sucrose into the cell. Using different symbols (circles for oxygen, squares for sucrose, and triangles for potassium ions), show the relative concentrations (gradients) of these substances on the inside and outside of the cell. For example, to show that oxygen enters the cell by going “down” its gradient, you would draw more circles on the outside of the cell than inside the cell. Be sure to show and label membrane proteins when appropriate, and show the electric membrane potential using “+”s (pluses) on one side and “-”s (minuses) on the other side of the membrane. Also show the proton pump which uses ATP as a source of energy.
When LDL (low density lipoprotein) is taken up by cells during pinocytosis, which of the following steps in the processing of LDL and its receptor protein does not occur? LDL attaches to LDL receptors, which form clathrin-coated vesicles the vesicles fuse with endosomes, and LDL receptors are recycled LDL is digested in lysosomes, releasing cholesterol to the cytoplasm the endosomes fuse with lysosomes for digestion of the LDL LDL receptors are digested in the lysosomes along with the LDL
Which of the following (could be more than one) would not be a rational explanation for why the three-dimensional structure of a protein is driven and stabilized largely by noncovalent rather than covalent bonds?a) Proteins may be degraded for energy, and if their three-dimensional structures were heldtogether by mostly covalent bonding, this might be too difficult to accomplishb) Proteins will need to be unfolded to cross biological membrane, and if their three-dimensionalstructures were held together by mostly covalent bonding, this might be too difficult toaccomplish.c) Protein function (transport, enzyme catalysis, etc...) may require flexibility in the three-dimensional structure to allow for conformational change, and if protein three-dimensionalstructure were held together by mostly covalent bonding, this might be too difficult toaccomplish.d) All of the answer choices are rational explanations for why the three-dimensional structure of protein is driven and stabilized largely…
Draw a hydropathy plot and a 2D protein cartoon for a protein that passes through the lipid bilayer 6 times..
Of the following cell membrane lipids, which one prefers to reside in the inner leaflet (or inner half) of the membrane bilayer, AND has an overall neutral charge at physiological pH (7.4)? a) PE (phosphatidylethanolamine) is inner-leaflet with an overall neutral charge at pH 7.4 b) SM (sphinogomyelin) is inner-leaflet with an overall neutral charge at pH 7.4 c) PS (phosephatidylserine) is inner-leaflet with an overall neutral charge at pH 7.4 d) PC (phosphatidylcholine) is inner-leaflet with an overall neutral charge at pH 7.4
"Although lipid molecules are free to diffuse in the plane of the bilayer, they cannot flip-flop across the bilayer unless enzyme catalysts called phospholipid translocators are present in the membrane", is true or false.

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