Why Are You Able to Repeatedly Contract and Relax Your

question 72

Multiple Choice

Why are you able to repeatedly contract and relax your muscles of respiration, allowing you to breathe in and breathe out?

• A) As soon as all of the Ca²⁺ stored in the lateral sacs of the sarcoplasmic reticulum is used up, muscle relaxation occurs.
• B) After the muscle cell becomes excited, acetylcholinesterase rapidly destroys acetylcholine.
• C) When there is no longer a local action potential in the muscle cell, Ca²⁺ is actively transported back into the lateral sacs of the sarcoplasmic reticulum, and muscle relaxation occurs.
• D) Both (b) and (c) above.
• E) All of these answers.

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Net Income

The amount of profit left over after all expenses and taxes have been subtracted from total revenue.

Depreciation Expense

The allocated portion of the total cost of a company's tangible assets that is charged to expense across the asset's useful life.

Net Income

Net income is the total earnings of a company after all expenses and taxes have been subtracted from total revenue.