4. Give an overview of how fatty acids are synthesised in vivo and explain how the...

4. Give an overview of how fatty acids are synthesised in vivo and explain how the process
is affected in diabetes. Precise details of the pathway are not required.
(10 marks – 300 words)

Solutions

Expert Solution

Fatty acid synthesis is the creation of fatty acids from acetyl-CoA and NADPH through the action of enzymes called fatty acid synthases. This process takes place in the cytoplasm of the cell. Most of the acetyl-CoA which is converted into fatty acids is derived from carbohydrates via the glycolytic pathway.

Fatty acid synthesis is a critical anabolic pathway in most organisms. In addition to being the major component of membranes, fatty acids are important energy storage molecules, and fatty acyl derivatives possess a variety of physiological functions, including post-translational modification of numerous proteins.

Fatty acids are normally synthesized from acetyl-CoA, a process that requires ATP, biotin, Mg++, and Mn++. Acetyl-CoA carboxylase, the rate-limiting enzyme in fatty acid biosynthesis, is inhibited by glucagon and epinephrine, and stimulated by insulin. Intermediates in fatty acid biosynthesis are attached to acyl carrier protein (ACP). Malonyl-CoA serves as an activated donor of acetyl groups in fatty acid biosynthesis. Propionate (C3) may be used in place of acetate (C2) as a priming molecule for fatty acid biosynthesis in adipocytes and in the lactating mammary gland. Fatty acid elongation beyond palmitate takes place in mitochondria, or on the smooth endoplasmic reticulum (SER). Animals are capable of synthesizing all of the FAs they need except for the essential FAs, which must be supplied through the diet. The hexose monophosphate shunt, malic enzyme, and cytoplasmic isocitrate dehydrogenase assist in providing NADPH for palmitate biosynthesis. Fatty acid biosynthesis occurs in adipocytes of ruminant animals, and in the liver of non-ruminant animals.

During diabetes, Insulin inhibits breakdown of fat in adipose tissue by inhibiting the intracellular lipase that hydrolyzes triglycerides to release fatty acids. Insulin facilitates entry of glucose into adipocytes, and within those cells, glucose can be used to synthesize glycerol.

gladiator answered 1 year ago

Next > < Previous

Related Solutions

Describe in words how fatty acids are released in the body AND how fatty acids arrive...

Describe in words how fatty acids are released in the body AND how fatty acids arrive at the appropriate cellular location for use (no structures). Beginning from this point, provide the details in words (names of structures, enzymes, cofactors, etc.) for one round of fatty acid degradation. Include the tissue and cellular locations for each part of the process of harvesting fatty acids for energy. What pathway does the primary product enter next? Provide details in words (names of structures, enzymes,...

Most of these fatty acids increase blood cholesterol levels by raising LDL cholesterol These fatty acids...

Most of these fatty acids increase blood cholesterol levels by raising LDL cholesterol These fatty acids raise LDL cholesterol while reducing beneficial HDL cholesterol These fatty acids generally lower LDL cholesterol and raise HDL cholesterol These fatty acids will lower LDL cholesterol, but in some people, they may also cause a decrease in beneficial HDL cholesterol MATCHING Trans Polyunsaturated Monounsaturated Saturated

Distinguish between ex vivo and in vivo gene therapy and give examples of each.

Explain the process of forward and reverse transport of fatty acids and cholesterol and the role...

Explain the process of forward and reverse transport of fatty acids and cholesterol and the role of cholesterol in the regulation of the transcription of the LDL receptor gene. Your answer should describe the relevant apolipoproteins and receptors

Every biochemistry student knows that most naturally occurring unsaturated fatty acids are "cis" fatty acids. Why...

Every biochemistry student knows that most naturally occurring unsaturated fatty acids are "cis" fatty acids. Why then do so many fat-containing foods come with the notation "contains no trans fats"? A) Vegetable oils contain polyunsaturated fatty acids prone to oxidation, which then convert them to trans fats. B) Olive oils, normally healthy oils, are converted to trans fat when cooked at high temperatures. Thus, olive oils are used only at low temperatures. C) Vegetable oils are often hydrogenated to form...

trace the route of biosynthesis and the storage of hlucose, fatty acids and amino acids

Unsaturated fatty acids are (more or less) oxidied than saturated acids. Which yields more energy? How...

Unsaturated fatty acids are (more or less) oxidied than saturated acids. Which yields more energy? How is acetyl-Coa used in liver cells? in what process/ what does it produce

Which of the following is NOT TRUE of unsaturated fatty acids?

Which of the following is NOT TRUE of unsaturated fatty acids? a. Unsaturated fatty acids tend to be liquid at room temperature because the bent chains that result from double bonds occupy more space than saturated fatty acids and do not pack together well. b. By definition unsaturated fatty acids are essential fatty acids.с. Inserting double bonds into a fatty acid chain is a strategy for adapting to cold weather. d. All fatty acids yield the same amount of energy (9 kcal per...

What is the numbering scheme for naming fatty acids.

How is LIPOGENESIS in adipose tissue regulated after eating a meal rich in FATTY ACIDS? (how...

How is LIPOGENESIS in adipose tissue regulated after eating a meal rich in FATTY ACIDS? (how does insulin, various substrate availability affect this)

Subjects