Substrate Transport into Skeletal Muscle

Questions and Answers

Match the following fatty acid transporters with their full names:

FAT/CD36 = Fatty acid translocase/cluster of differentiation 36 FABPpm = Plasma membrane associated fatty acid binding protein FATP1 = Family of fatty acid transport proteins 1 FATP4 = Family of fatty acid transport proteins 4

Match the following amino acid transporters with their full names:

SNAT2 = Sodium-coupled neutral amino acid transporter 2 LAT1 = L-type amino acid transporter 1 PAT1 = Proton-assisted amino acid transporter 1 CAT1 = Cationic amino acid transport 1

Match the following statements with the correct type of energy source:

Preferred source of energy for muscles after exercise = Glycogen Last resort source of energy for muscles = Protein Primary source of energy for muscles during exercise = Fat Quickly grabbed and stored by muscle after exercise = Glucose

Match the following fatty acid transport-related statements with the correct factor:

Stimulates FFA uptake in the muscle = Insulin and muscle contraction Regulates fatty acid transport into muscle = Transporters Determines the amount of FFAs that will move into the muscle = Concentration gradient Preferred method of fatty acid entry into muscle = Transporters Signup and view all the answers

Match the following fatty acid transporters with their functions:

FAT/CD36 = Fatty acid translocase FABPpm = Plasma membrane associated fatty acid binding FATP1 = Family of fatty acid transport proteins 1 FATP4 = Family of fatty acid transport proteins 4 Signup and view all the answers

Match the following amino acid transport-related statements with the correct factor:

Transports specific amino acids across the membrane = Each transporter Needed to build more proteins in the cell = Amino acids Metabolism can be tricky = Amino acids Acts as a fuel source when there is no carbs or fats left = Protein Signup and view all the answers

Match the following statements with the correct type of transport:

Passive method of fatty acid entry into muscle = Diffusion Regulated method of fatty acid entry into muscle = Transporters Preferred method of fatty acid entry into muscle = Transporters Method of amino acid transport into muscle = Transporters Signup and view all the answers

Match the following statements with the correct statement about CD36 and FATP4:

Most important for fatty acid transport into muscle = CD36 and FATP4 Stimulated by insulin and muscle contraction = CD36 and FATP1 Involved in fatty acid transport into muscle = All transport proteins Facilitate fatty acid uptake in the muscle = CD36 and FATP4 Signup and view all the answers

Match the type of protein with its function:

Receptor proteins = Sensitive to specific chemicals in the ECF Carrier proteins = Move molecules across the cell membrane Channel proteins = Not mentioned in the content Transporter proteins = Help polar molecules move across the cell membrane Signup and view all the answers

Match the term with its description:

Facilitated diffusion = Type of carrier-mediated transport that requires energy Diffusion = Movement of molecules from high to low concentration Carrier-mediated transport = Use of proteins to help polar molecules move across the cell membrane Passive transport = Not mentioned in the content Signup and view all the answers

Match the component of the phospholipid membrane with its characteristic:

Hydrophilic head = Faces the outside of the cell Hydrophobic tails = Faces the inside of the cell Phosphate group = Part of the glycerol molecule Fatty acid = Part of the phospholipid molecule Signup and view all the answers

Match the level of substrate uptake with its description:

Energy demand = By the contracting muscle Delivery of substrates = To the muscle Transport of substrates = Into the muscle by specific transporters Utilization of substrates = Not mentioned in the content Signup and view all the answers

Match the term with its function in cellular transport:

Receptor site = Binds to the target molecule Carrier protein = Changes shape to move the molecule across the membrane Channel = Forms a pore for molecules to pass through Facilitated transporter = Uses energy to move molecules against their gradient Signup and view all the answers

Match the type of molecule with its ability to cross the cell membrane:

Lipid = Can dissolve in the lipid bilayer and move across without a transporter Polar = Needs the help of transporters or channels to get across the cell membrane Hydrophobic = Faces the outside of the cell Hydrophilic = Faces the inside of the cell Signup and view all the answers

Match the term with its description related to cellular transport:

Ligand = The target molecule that binds to the carrier protein Concentration gradient = The direction of molecule movement from high to low concentration Energy expenditure = Required for facilitated diffusion Selective permeability = The property of the lipid bilayer that allows only certain molecules to pass through Signup and view all the answers

Match the component of the phospholipid molecule with its characteristic:

Glycerol = Has a modified phosphate group Fatty acid = Has a hydrophobic tail Phosphate group = Has a hydrophilic head Hydrophilic head = Faces the outside of the cell Signup and view all the answers

Match the glucose transport regulatory sites with their descriptions:

Glucose supply = Dependent on blood supply to the muscle and the concentration of glucose in the blood. Glucose transport = Storage of glucose as glycogen or the oxidation of glucose in the cell. Glucose metabolism = Via facilitated diffusion, dependent on the presence of GLUT4 and GLUT1. None of the above = Not a regulatory site. Signup and view all the answers

Match the statements with the correct GLUT transporter:

GLUT4 = Determines the level of transport of glucose into the cell and increases during exercise. GLUT1 = Increases during exercise and after feeding. Insulin receptor = Triggers the uptake of glucose by binding to the GLUT4 transporter. None of the above = Not a GLUT transporter. Signup and view all the answers

Match the physiological processes with their triggers:

Glucose uptake = Insulin binding to the insulin receptor. GLUT4 transporters to the membrane = Muscle contraction. Increased metabolic demand = Hormones affecting glucose and FFA into the bloodstream. Glycogenesis = Activation of the storage or metabolic pathways specific to glucose. Signup and view all the answers

Match the substrates with their primary sources during exercise:

Glucose = Circulation and intracellular stores. FFA = Circulation and intracellular stores. Glycogen = Intracellular stores only. ATP = Generated in the cell from glucose oxidation. Signup and view all the answers

Match the statements with the correct effect on glucose transport:

Increased insulin = Increases the uptake of glucose. Increased muscle contraction = Increases GLUT4 transporters to the membrane. Decreased blood glucose concentration = Decreases glucose supply to the muscle. Increased GLUT1 = Increases glucose metabolism. Signup and view all the answers

Match the fuels with their relative contributions during exercise:

Circulating fuels = 20-30% of fuels being used at 40% VO2max. Intracellular fuels = 70-80% of fuels being used at 40% VO2max. Glucose only = Major fuel source during high-intensity exercise. FFA only = Major fuel source during low-intensity exercise. Signup and view all the answers

Match the physiological processes with their effects on GLUT4:

Exercise = Increases the content of GLUT4 in the cells. Feeding = Increases the content of GLUT4 in the cells. Insulin binding = Triggers the transport of GLUT4 to the membrane. Muscle contraction = Decreases the content of GLUT4 in the cells. Signup and view all the answers

Match the statements with the correct regulatory mechanism:

Changes to insulin = Affects the availability of glucose and FFAs. Max rate of substrate transport = Reached at low intensity exercise. Increased metabolic demand = Driven by working muscle. GLUT4 transporters = Regulated by muscle contraction only. Signup and view all the answers