Question

1) Describe how triglycerides can be used in oxidative phosphorylation

2) Describe the pathway of beta-oxidation and the products it produces

Answer 1

1). Answer :

Adipose tissue contains adipocytes that store triglycerides in the intracellular vesicles. In response to homeostatic pressures the triglycerides are converted to glycerol and fatty acids. The fatty acids can then leave the cell, enter the blood and be transported to other tissues which need the fatty acids to synthesize ATP. Fatty acids from the blood enter the cytosol of cells by facilitated diffusion and then enter the matrix of mitochondria. I. Mitochondria the fatty acids are broken down in a process called beta oxidation to acetyl coA , NADH and FADH2. The acetyl coA then enters the Krebs cycle which results in the further production of NADH and FADH2.

2). Answer :

Beta oxidation is the catabolic process by which fatty acid molecules are broken down in the cytosol in prokaryotes and in the mitochondria in eukaryotes to generate acetyl -coA, which enters the citric acid cycle and NADH and FADH2, which are co-enzymes used in the electron transport chain. It is named as such because the beta carbon of the fatty acid undergoes oxidation to a carbonyl group. Beta oxidation is primarily facilitated by the mitochondrial trifunctional protein, an enzyme complex associated with the inner mitochondrial membrane although very long chain fatty acids are oxidized in peroxisomes.

Each beta oxidation cycle yields 1 FADH2, 1NADH and 1 acetyl -coA and water, which in terms of energy is equivalent to 17 ATP molecules .