Final answer:
Insulin promotes glucose uptake by cells, providing energy and building blocks for fatty acid synthesis. It also activates key enzymes involved in fatty acid synthesis.
Step-by-step explanation:
Insulin has multiple effects on fatty acid synthesis. It promotes the uptake of glucose by body cells, which is then used in cellular respiration. This provides the necessary energy and building blocks for fatty acid synthesis. Additionally, insulin activates key enzymes involved in fatty acid synthesis, such as acetyl-CoA carboxylase, which catalyzes the production of malonyl-CoA, an important precursor for fatty acid synthesis.