Final answer:
Blocking transport across a cell's membranes would shorten its life span because nutrients and oxygen wouldn't reach the cell, causing it to starve.
Step-by-step explanation:
Blocking all transport across a cell's membranes would shorten the cell's life span because it would prevent essential processes from occurring. Option 2 is the most accurate explanation: without transport through the cell membranes, nutrients and oxygen wouldn't reach the cell, causing it to starve. This would lead to the cell's death and a shorter life span.
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