Of the following cell membrane lipids, which one 1) prefers to reside in the inner leaflet (or inner half) of the membrane bilayer, AND 2) is not zwitterionic at physiological pH (7.4)? 1. SM (sphingomyelin) is inner-leaflet & NOT zwitterionic 2. PC (phosphatidylcholine) is inner-leaflet & NOT zwitterionic 3. PS (phosphatidylserine) is inner-leaflet & NOT zwitterionic  4. 2 of these 3 responses are correct

Would you expect this molecule to spontaneously assemble into a liposome? Why or why not? CH₂ CH- CH₂- 0=0 C. Yes: this compound contains oxygen, and all oxygen-containing compounds are very polar (amphipathic). No: this compound is roughly conical-shaped, and thus would have a higher tendency to form a micelle than a liposome. No: this compound would have a high tendency to repel water, and thus would force a liposome to form a micelle. No: this compound is not strongly amphipathic and thus could not spontaneously form a liposome in aqueous solution. No: this compound is hydrophilic and so would dissolve before it could form a liposome. Yes: this compound is cylindrical in shape and thus could spontaneously assemble into a liposome.

1)What is the second type of lipid that plays a major role in the plasma membrane? This lipid does not have polar and nonpolar regions (its not amphiphilic) but plays a critical role in membrane permeability. A)Triglycerdies B) Steriod hormones c) cholesterol 2) In _______________, a single substrate/solute move from a high concentration area to a lower concentration are without the aid of any additional molecules. A) Diffusion B)Facilitated diffusion C) Cotransport 3)Channel proteins require a confirmational change in order to properly function. A) Hydrophilic B) ionic C) Polar

Average skin (epidermal) cell has a diameter of 30 micrometers.  The majority of the surface of the human body is covered by skin cells.  The average surface area of an adult male is 1.9 m2 and an adult female is 1.6 m2.   1. Use this formula to determine the area an average skin cell covers: Area = π (radius)2          Plug the radius (1/2 the diameter) of an average skin cell into the equation. area of an average skin cell  ____________________ 2. Next, convert your surface area (average male or female) from m2 into mm2 your surface area____________________ 3. Then, divide your surface area by the average area of a skin cell.                                     number of skin cells covering your body  ____________________

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.

Where is the KV1.1 (a membrane protein) polypeptide synthesized in the cell?  (word bank: cytoplasm, nucleus, rough ER, smooth ER, mitochondria)    The amino acids that line the outside of the KV1.1 protein (i.e., those in contact with the phospholipid bilayer's fatty acids tails) are more likely to be _______(word bank: hydrophobic, hydrophilic) The KV1.1 protein utilizes __ transport to move the K+ ions across the membrane.  (word bank: active, passive) This disease can be caused by missense mutations.  In general, how specifically would a missense mutation affect the KV1.1 protein?

Please answer both, thank you

3)What is the second type of lipid that plays a major role in the plasma membrane? This lipid does not have polar and nonpolar regions (its not amphiphilic) but plays a critical role in membrane permeability. A)phospholipids b) steroid hormones c) Cholesterol 4)Which one of the following influences the rate at which diffusion can occur? Size of the concentration gradient Mass of the molecule Distance All of the above affect diffusion None of the above affect the diffusion rate

Consider the amino acids on the image below. Which of the following amino acids would be most likely to be found in the part of an integral membrane protein that is located within the membrane? (Select all answers that apply.) Asparagine (Asn)   Lysine (Lys)   Phenylalanine (Phe)   Valine (Val)   Glutamic acid (Glu)  Methionine (Met)

In general terms, what would you expect to be different about the permeability of a lipid bilayer made of phospholipids (modern cells) and a bilayer made of fatty acids (protocell)?