Open Question
Which of the following cannot pass through the membrane without the help of a membrane protein?a. carbon dioxide;b. water;c. oxygen;d. charged molecules
6. The Membrane
Active Transport
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How are primary and secondary active transport related?
A
They both use ATP to move molecules
B
Primary active transport establishes a concentration gradient, but secondary active transport doesn't
C
Secondary active transport uses the concentration gradient established by primary active transport
D
Primary active transport moves one molecule, but secondary active transport moves two
E
None of the above
Verified step by step guidance1
Begin by understanding the concept of active transport, which is the movement of molecules across a cell membrane using energy, typically in the form of ATP.
Primary active transport directly uses ATP to move molecules against their concentration gradient. This process establishes a concentration gradient across the membrane.
Secondary active transport, also known as co-transport, does not directly use ATP. Instead, it relies on the concentration gradient established by primary active transport to move molecules.
In secondary active transport, the energy from the concentration gradient of one molecule is used to transport another molecule against its gradient. This often involves the movement of two molecules simultaneously.
Recognize that primary and secondary active transport are interconnected processes, where primary active transport sets up the conditions necessary for secondary active transport to occur.
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Active Transport practice set
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