Lipids 3 Flashcards Preview

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Flashcards in Lipids 3 Deck (21)
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1
Q

Where can fatty acids be found?

A

In our diet (essential fatty acids) and from the synthesis of excess carbohydrates and protein components.

2
Q

Where are the 3 places fatty acid synthesis occurs?

A

Liver
Lactating mammary gland
Adipose tissue

In the cytosol of all.

3
Q

Where is acetyl CoA formed?

A

In the mitochondria so needs transported to the cytosol.

4
Q

What part of acetyl CoA can not pass through the mitochondrial membrane?

A

CoA

5
Q

What binds with acetyl CoA to allow it to pass through the mitochondrial membrane and what enzyme is used?

A

Oxaloacetate to make citrate. Citrate synthase.

6
Q

What enzyme is used in the following reactions:

Oxaloacetate -> Malate
Malate -> Pyruvate
Pyruvate -> Oxaloacetate

A

Malate dehydrogenase
Malate Enzyme
Pyruvate Carboxylase

7
Q

What is acetyl CoA carboxylase and what is its function?

A

Key regulatory enzyme which is activated by citrate signalling there is enough glucose.

8
Q

What deactivates acetyl CoA carboxylase?

A
Palmitoyl CoA (enough fatty acid has been made).
Glucagon/epinephrine.
9
Q

What is the overall reaction for palmitate?

A

8 Acetyl CoA + 14 NADPH + 14 H+ + 7 ATP -> Palmitate + 8 CoA + 14 NADP+ + 7 ADP + 7 Pi + 7 H2O

10
Q

How many times is the elongation cycle repeated?

A

6 using Malonyl CoA to produce Palmityl ACP.

11
Q

The intermediates in fatty acid synthesis are ______ linked to the acyl carrier protein.

A

Covalently

12
Q

Any further modifications of palmitate or dietary fatty acids occurs in the ______ and the ______ by diverse enzymes.

A

Mitochondria, endoplasmic reticulum.

13
Q

What is the process of fatty acid synthesis?

A

Acetyl CoA -> Fatty Acid -> Triacylglycerol -> VLDL -> Adipose tissue

14
Q

Define steroid hormone.

A

Chemical substances that serve as chemical messengers.

15
Q

Define cholesterol.

A

Starting material for the synthesis of steroid hormones.

16
Q

Define eicosanoids.

A

Are derived from a 20-carbon unsaturated fatty acid and are synthesised around the body.

17
Q

What is the function of sterols such as cholesterol?

A

Component of cell membrane
Precursor to other substances
Synthesis is mainly in the liver and only found in animal foods

18
Q

Define statins.

A

Inhibit HMG-CoA reductase that is essential in cholesterol synthesis.

19
Q

Give the 6 thing eicosanoids regulate.

A
Inflammatory response
Pain and fever
Blood pressure
Blood clotting induction
Many reproductive functions and menstrual cramps
Sleep/Wake cycle
20
Q

Define Cox inhibitors.

A

Anti-inflammatory and fever reducing property of aspirin due to inhibition of Cox 1 enzyme and prostaglandin synthesis.

21
Q

What is the function of aspirin?

A

Inhibits thromboxanes that cause clotting.