Refer to the Figure Shown

question 6

Multiple Choice

Refer to the figure shown.
Which substance is mostly likely being pumped at A?

• A) Na⁺
• B) H⁺
• C) K⁺
• D) ATP

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Definitions:

Unilateral Contract

A promise made by one party in exchange for the performance of a task or action by another party.

Past Consideration

A benefit already provided or an action already performed, which cannot legally constitute consideration for a current contract.

Consideration

A value that is exchanged between parties in a contract, making the agreement legally binding.

Promissory Estoppel

A legal principle that prevents a party from withdrawing a promise made to another party, if the latter has reasonably relied on that promise to their detriment.