Describe myoglobin.Multiple choice question.A molecule that stores oxygen in musclesA protein of the thick myofilaments.An enzyme found in the synaptic cleftCarbohydrate that provides the muscle cell with energyA hormone that triggers contraction

Oxygen storage in muscle cells is mediated by the protein myoglobin, which consists of multiple α-helices held in a specific conformation.  Each myoglobin protein binds to one heme cofactor, which in turn can bind one oxygen molecule.  The bound oxygen can be released when a muscle cell's oxygen needs are not met by the blood.  The oxygen binding curve for myoglobin is shown in Figure 1, with the p50 (the oxygen partial pressure at which 50% of myoglobin molecules are bound to oxygen) value shown.Figure 1  Oxygen binding curve of myoglobinMyoglobin samples were exposed to different concentrations of the detergent N,N-dimethyl-N-dodecylglycine betaine (EBB).Figure 2  Structure of N,N-dimethyl-N-dodecylglycine betaine (EBB).Oxygenated heme absorbs light at 409 nm when bound to myoglobin.  This absorbance shifts slightly when heme is not bound to myoglobin.  Figure 3 shows that as the concentration of EBB increases under atmospheric oxygen levels, the absorbance of the solution at 409 nm decreases, indicating that EBB causes partial myoglobin unfolding and heme release.Figure 3  Absorbance of a myoglobin solution at 409 nm as a function of EBB concentrationCircular dichroism revealed that the α-helices within myoglobin remain largely intact at all EBB concentrations.  Thermodynamic studies revealed that the standard Gibbs free energy of heme dissociation from myoglobin is approximately 8,000 kJ/mol.Kohn, E.M., Lee, J.Y., Calabro, A., Vaden, T.D., & Caputo, G.A. (2018). Heme dissociation from myoglobin in the presence of the zwitterionic detergent N,N-dimethyl-N-dodecylglycine betaine: Effects of Ionic Liquids. Biomolecules, 8(4), 126. Question 33For myoglobin to bind oxygen, which of the following must be true?The partial pressure of oxygen must be above 0.25 kPa.Myoglobin must have an intact tertiary structure.Myoglobin must exist as a holoprotein.A.I and II onlyB.I and III onlyC.II and III onlyD.I, II, and III

What is the function of myoglobin in the muscle cell?Group of answer choicesNone of these are functions of myoglobin.It stores amino acids needed for building myofilaments.It stores calcium ions inside the muscle cell.It serves as an immediate reserve source of oxygen for the muscle cell.It serves as an immediate reserve source of energy for the muscle cell.

The protein located in muscle cells that delivers oxygen directly to the mitochondria is Blank______.Multiple choice question.myosinmyoglobinhemoglobinATP

The function of myoglobin in muscle cells is to Blank______.Multiple choice question.release calcium ions from the sarcoplasmic reticulumdeliver oxygen directly to mitochondriaaid in muscle contraction by interacting with actinaid in muscle contraction by interacting with myosin

Which molecule is stored in muscle fibers and can supply quick energy for ATP synthesis?Multiple choice question.MyosinMyoglobinCreatine phosphateAcetylcholine