The helix, Tyr-Arg-Glu-Leu-Val-Asp-Ala-Ile-Leu-Arg-Glu-Val-Phe-Thr-Lys-Arg-Gly, is present in the voltage gated sodium channel. Where would this helix be found? In the membrane, exposed to the solution, or somewhere else? Use a helical wheel to explain why

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)

The cell membrane is both fluid and asymmetrical. Discuss asymmetry of the plasma membrane, as well as the enzyme involved. Explain properties that contribute to the fluidity of the cell membrane?

a) At what pH will you try to bind lysozyme to a cation exchanger?   b) Is it possible to perform this binding even at a different pH than the one you mentioned in section a? Explain your answer.   c) Is it possible to bind lysozyme to an anion exchanger as well? If so, at what pH?

Histamine acts by binding to specialized membrane proteins called histamine H 1 receptors. These receptors, found in specific cells, are integral membrane proteins that possess seven transmembrane a-helical regions. The amino terminus of the protein is extracellular, while the C-terminus is cytoplasmic. The binding of histamine to the extracellular portion of the H 1 receptor prompts a conformational change in the intracellular C-terminus region of the protein. This conformational change triggers numerous intracellular signaling events that stimulate the immune response in cells containing the receptor. There are numerous anti-histamine drugs available commercially. Some of the most popular are shown here side by side with histamine: HCHS NH- Allegra H2N histamine Claritin Propose a reasonable mode of action by which these antihistamines exert their activity. Include relevant details about the system of your own choosing.

Phospholipids (Which is charged, what is the functional significance? Are they preferentially located on cytosolic or extracellular lipid monolayer? What is the functional significance of plasma membrane asymmetry?)

Arrange the following terms in order of decreasing specialization: oligopotency, pleuripotency, unipotency, multipotency

Would an extracellular signal receptor protein mostly likely consist of type 1 or type 2 alpha helices? Explain your reasoning

The hemoglobin in the fetus (HbF) is a structural variant of the hemoglobin in the mother (HbA). HbA is a tetrameric protein complex consisting of two α-globin and two β-globin subunits. HbF is made up of two αglobin and two γ-globin subunits, where the γ-globins are similar to the β-globins but γglobins have lower affinity for 2,3- bisphosphoglycerate or BPG. Studies of oxygen transport in pregnant mammals show that the oxygen-saturation curves between the red blood cells of the fetus and the mother are markedly different. 1. The shape of hemoglobin binding curves is: hyperbolic or sigmoidal 2. a) Based on the binding curves, determine the dissociation constant (Kd) for each hemoglobin complex. (Show correct units.) Kd of HbF + BPG: ________________ Kd of HbA + BPG: _____________________ b) Which has a higher affinity for oxygen? HbF+BPG HbA+BPG 3. a) How many BPG molecule(s) is/are expected to bind one hemoglobin complex? 1 2 3 4 b) BPG binding preferentially stabilizes which state…

Which fibrous protein is found in connective tissue and consists of 3 left-handed helices twisted together?