Question

what is the rate-limiting step for transforming linoleic and alpha linolenic acid?
○ delta-5 desaturase
○ delta-4 desaturase
○ delta-6 desaturase
○ lipoxygenase

Explanation:

In the metabolism of linoleic and alpha - linolenic acid (polyunsaturated fatty acids), the rate - limiting step for their transformation is catalyzed by Delta - 6 desaturase. This enzyme is responsible for introducing a double bond at the delta - 6 position during the desaturation process, and its activity often limits the overall rate of the metabolic pathway for these fatty acids. Delta - 5 desaturase, Delta - 4 desaturase, and lipoxygenase are not the rate - limiting enzymes for the transformation of these specific fatty acids.

Answer:

C. Delta - 6 desaturase (assuming the options are labeled A: Delta - 5 desaturase, B: Delta - 4 desaturase, C: Delta - 6 desaturase, D: Lipoxygenase)