CELL RESPIRATION
STRUCTURE OF THE MITOCHONDRION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the outer membrane is freely permeable to molecules such as ATD, NAD, and coenzyme A
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the membrane is impermeable
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requires all molecules and ions to have special membrane transporters to gain access to the matrix
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all the above
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Detailed explanation-1: -Porins are beta barrel proteins that cross a cellular membrane and act as a pore, through which molecules can diffuse. Unlike other membrane transport proteins, porins are large enough to allow passive diffusion, i.e., they act as channels that are specific to different types of molecules.
Detailed explanation-2: -Porins are involved in the exchange of nutrients over the outer membrane of Gram-negative bacteria but are also involved in pathogenesis.
Detailed explanation-3: -Mitochondrial outer membrane permeability is conferred by a family of porin proteins. Mitochondrial porins conduct small molecules and constitute one component of the permeability transition pore that opens in response to apoptotic signals.
Detailed explanation-4: -Porins also possess an internal hydrophilic channel or pore that permits the passage of small macromolecules, such as glucose or maltose amongst others, from the external environment to the cell interior.