Question

How do FAs of different carbon lengths cross into the mitochondrial matrix for oxidation? 1) Small FAs of 10 carbons or fewer can freely diffuse through the membrane. 2) Large FAs are cleaved into two smaller units that are actively transported across the membrane. 3) A membrane-bound transferase catalyzes the conversion of long-chain FAs to FA-carnitine esters, which are transported across the membrane via a specific carrier. 4) The breakdown of large FAs starts outside the matrix, allowing for smaller particles to pass easily through the membrane. How do FAs of different carbon lengths cross into the mitochondrial matrix for oxidation? 1) Small FAs of 10 carbons or fewer can freely diffuse through the membrane. 2) Large FAs are cleaved into two smaller units that are actively transported across the membrane. 3) A membrane-bound transferase catalyzes the conversion of long-chain FAs to FA-carnitine esters, which are transported across the membrane via a specific carrier. 4) The breakdown of large FAs starts outside the matrix, allowing for smaller particles to pass easily through the membrane. Only statements 1 and 4 are correct. Only statements 1 and 3 are correct. Only statements 1, 2 and 3 are correct. All of the listed statements are correct.

Answer 1

Only statements 1 and 3 are correct.

1) Small FAs of 10 carbons or fewer can freely diffuse through the membrane. ----------> TRUE

2) Large FAs are cleaved into two smaller units that are actively transported across the membrane. -----> FALSE (large FAs enter via carnitine transporter).

3) A membrane-bound transferase catalyzes the conversion of long-chain FAs to FA-carnitine esters, which are transported across the membrane via a specific carrier. ---------------> TRUE.

4) The breakdown of large FAs starts outside the matrix, allowing for smaller particles to pass easily through the membrane. ---------> FALSE