Intracellular concentrations in resting muscle are as follows: fructose6-phosphate, 1.0 mM; fructose-1,6-bisphosphate, 10 mM; AMP, 0.1 mM;ADP, 0.5 mM; ATP, 5 mM; and Pi, 10 mM. Is the phosphofructokinasereaction in muscle more or less exergonic than under standard conditions?By how much?

Rat heart muscle operating aerobically fills more than 90% of its ATP needs by oxidative phosphorylation. If each gram of tissue consumes O2 at the rate of 12.0 micromol/min, with glucose as the fuel source. (a) Calculate the rate at which the heart muscle consumes glucose and produces ATP. (b) Consider an alternate scenario – what would be the rate of consumption if the energy source was a solely triglycerides whose fatty acyl chains were each 14-C in length and saturated? (Assume the O2 consumption rate remains at 12.0 micromol/min) (c)  For a steady-state concentration of ATP of 6.0 micromol/g of heart muscle tissue, calculate the time required (in seconds) to completely turn over the cellular pool of ATP if glucose us used as the sole fuel source. What does this result indicate about the need for tight regulation of ATP production? (Note: Concentrations are expressed as micromoles per gram of muscle tissue because the tissue is mostly water.)

After prolonged exercise the body becomes depleted of glycogen. Which type of diet will lead to a quicker replenishment of muscle glycogen, a high fat, high protein diet or a high carbohydrate diet?Explain.

Discuss the similarities and differences by which Ca2+ activity is involved in initiating muscle contraction in skeletal versus smooth muscle fibers (hint: include Ca2+ sources, proteins it binds to, and signaling cascade it activates leading to contraction). (please explain in sentences, max 12 sentences)

Which of the following is the correct summary of the anaerobic breakdown of glucose in the skeletal muscle?   Glucose + ADP + Pi ⟶ lactate + ATP   Glucose + 2ADP + 2Pi ⟶ 2 lactate + 2ATP   Glucose + 2ADP + 2Pi + 2NAD+ ⟶ 2 pyruvate + 2ATP + 2NADH + 2H+   Glucose + ADP + Pi ⟶ pyruvate + ATP   Glucose + 2ADP + 2Pi ⟶ 2 pyruvate + 2ATP

Succinylcholine act as adepolarising agent that prevents repolarization of the somatic motor neuron. Thus, no further ACh is released until drug is cleared. Name another site within the MNJ we could target to prevent muscle contraction, and explain why this would work.

T/F Type I collagen fibers, that consist of collagen triple helices aligned side-by-side, are strengthened by covalent cross-links between amino acid side chains of different collagen triple helices. True O Failse

Briefly describe the concept of steady state in a regular body cell. What is the role of Na+/K+ - ATPase? How this state can be changed in patients with hypokalemia?

In considering active transport by Na + -K + -ATPase at body temperature (37 o C), 3 Na+ are pumped out of the cell and 2 K + are pumped in for each ATP that is hydrolyzed to ADP + P i . Given that underyour experimental conditions, the DG for ATP hydrolysis is -10 kcal/mol, and that V is -60 mV, and that the pump maintains the internal Na + at 10mM, external Na + at 120 mM, internal K + at 120 mM and external K + at 8mM, what is the efficiency of the pump (i.e., what fraction of the energy available from ATP hydrolysis is required to drive transport at the provided levels)?

Define hypertrophy of skeletal muscle. Explain skeletal muscle adaptations to strength training (over time, not acute).  What are the mechanisms of action?  What hormones are involved?  What cell signaling occurs to produce hypertrophy? Identify two principles of resistance training and explain how they contribute to skeletal muscle adaptation. Provide at minimum, two reputable resources to back up your claims.