Lipids 3 Flashcards
Where can fatty acids be found?
In our diet (essential fatty acids) and from the synthesis of excess carbohydrates and protein components.
Where are the 3 places fatty acid synthesis occurs?
Liver
Lactating mammary gland
Adipose tissue
In the cytosol of all.
Where is acetyl CoA formed?
In the mitochondria so needs transported to the cytosol.
What part of acetyl CoA can not pass through the mitochondrial membrane?
CoA
What binds with acetyl CoA to allow it to pass through the mitochondrial membrane and what enzyme is used?
Oxaloacetate to make citrate. Citrate synthase.
What enzyme is used in the following reactions:
Oxaloacetate -> Malate
Malate -> Pyruvate
Pyruvate -> Oxaloacetate
Malate dehydrogenase
Malate Enzyme
Pyruvate Carboxylase
What is acetyl CoA carboxylase and what is its function?
Key regulatory enzyme which is activated by citrate signalling there is enough glucose.
What deactivates acetyl CoA carboxylase?
Palmitoyl CoA (enough fatty acid has been made). Glucagon/epinephrine.
What is the overall reaction for palmitate?
8 Acetyl CoA + 14 NADPH + 14 H+ + 7 ATP -> Palmitate + 8 CoA + 14 NADP+ + 7 ADP + 7 Pi + 7 H2O
How many times is the elongation cycle repeated?
6 using Malonyl CoA to produce Palmityl ACP.
The intermediates in fatty acid synthesis are ______ linked to the acyl carrier protein.
Covalently
Any further modifications of palmitate or dietary fatty acids occurs in the ______ and the ______ by diverse enzymes.
Mitochondria, endoplasmic reticulum.
What is the process of fatty acid synthesis?
Acetyl CoA -> Fatty Acid -> Triacylglycerol -> VLDL -> Adipose tissue
Define steroid hormone.
Chemical substances that serve as chemical messengers.
Define cholesterol.
Starting material for the synthesis of steroid hormones.
Define eicosanoids.
Are derived from a 20-carbon unsaturated fatty acid and are synthesised around the body.
What is the function of sterols such as cholesterol?
Component of cell membrane
Precursor to other substances
Synthesis is mainly in the liver and only found in animal foods
Define statins.
Inhibit HMG-CoA reductase that is essential in cholesterol synthesis.
Give the 6 thing eicosanoids regulate.
Inflammatory response Pain and fever Blood pressure Blood clotting induction Many reproductive functions and menstrual cramps Sleep/Wake cycle
Define Cox inhibitors.
Anti-inflammatory and fever reducing property of aspirin due to inhibition of Cox 1 enzyme and prostaglandin synthesis.
What is the function of aspirin?
Inhibits thromboxanes that cause clotting.
