Fats Flashcards
What are the main products of ß-oxidation of fatty acids?
a. Acetyl CoA
b. Carbon dioxide
c. Acyl-CoA
d. NADH
a. Acetyl CoA
d. NADH
Select all that are correct about de novo lipogenesis Select one or more: a. Creation of fat from carbohydrate b. Creation of protein from fat c. Creation of carbohydrate from fat d. Acetyl co A is important e. Acetyl co A is not important
a. Creation of fat from carbohydrate
d. Acetyl co A is important
Monounsaturated fats have how many double bonds: Select one: a. 0 b. 1 c. >1 d. 2
1
What percentage of the diet should be made up of fat in the general population? Select one: a. 5-20 % b. 15-30 % c. 35-50 % d. 25-40 %
b. 15-30 %
Which of these fat locations in the body carries the highest health risk? Select one: a. buttocks b. thighs c. hips d. abdomen
d. abdomen
A diacylglycerol contains Select one: a. One fatty acid and a glycerol b. Two fatty acids and a glycerol c. Three fatty acids and a glycerol d. None of these answers are correct
b. Two fatty acids and a glycerol
After fatty acids have been released from fat cells, what is the name of the protein carrier that transports them in blood? Select one: a. Acetyl-CoA b. Haemoglobin c. Apoprotein A1 d. Albumin
d. Albumin
Intramuscular triacylglycerol
Select one:
a. is broken down by a muscle specific hormone sensitive lipase
b. is an important fuel during exercise
c. is increased in endurance trained athletes and in obesity
d. all answers are correct
d. all answers are correct
Hormone sensitive lipase is activated by a high concentration of:
Select one:
a. insulin, adrenaline and leptin
b. insulin, phosphofructokinase and adrenaline
c. phosphofructokinase, leptin and calcium ions
d. calcium ions, leptin and adrenaline
d. calcium ions, leptin and adrenaline
How are long chain fatty acids transported through the body? Select one: a. Facilitated diffusion b. Within a chylomicron c. Secondary active transport d. Simple diffusion
b. Within a chylomicron
Transport of fatty acids across the inner mitochondrial membrane is dependent upon Select one: a. creatine b. carnitine c. Fatty acid binding protein (FABP) d. creatinine
b. carnitine
Which is involved in the transport of short chain fatty acids around the blood Select one: a. Chylomicron b. LDL c. Albumin d. VLDL
c. Albumin
Hormone sensitive lipase is a hormone which is present in an active and inactive form. Which enzyme turns the inactive form int the active form? Select one: a. protein dehydrogenase b. Protein phosphatase c. protein isomerase d. protein kinase
d. protein kinase
What is LPL Select one: a. Hormone sensitive lipase b. Lipoprotein lipase c. Low density lipoprotein d. Lipoprotein lipolysis
b. Lipoprotein lipase
Increased acetyl-coa will inhibit what? Select one: a. pyruvate dehydrogenase complex b. lipolysis c. contraction d. fatty acid oxidation
a. pyruvate dehydrogenase complex
Increased glycogenolysis in exercise is likely due to: Select one: a. increased ADP b. decreased ATP c. Increased AMP d. decreased AMP
c. Increased AMP
Inhibition of PFK will
Select one:
a. inhibit fat oxidation
b. inhibit fat oxidation and inhibit carbohydrate oxidation
c. inhibit carbohydrate oxidation and glycolysis
d. inhibit fat oxidation and glycolysis
c. inhibit carbohydrate oxidation and glycolysis
What effect will a reduction in FAD have on flux through beta oxidation? Select one: a. have no effect b. increase it c. reduce it
c. reduce it
Which of these are not required for the PDC reactions? Select one: a. ATP b. NAD c. FAD d. CoA
a. ATP
What is the difference between saturated and unsaturated fatty acids?
Saturated fatty acids have all single bonds between carbons
Unsaturated fatty acids have one or more double carbon bonds
Production of excessive amounts of acetyl CoA molecules leads to the synthesis of….
fatty acids only
Which of the following compounds cannot be formed from fatty acids?
a. Ketones
b. Glucose
c. Acetyl CoA
d. Carbon dioxide
b. Glucose
All of the following may serve as precursors for oxaloacetate synthesis except
a. fat.
b. starch.
c. glucose.
d. protein.
a. fat.
How does the liver convert excess carbohydrate to fat (5 steps)?
1) Glycolysis converts glucose into pyruvate.
2) Pyruvate dehydrogenase converts pyruvate into acetyl CoA via the link reaction.
3) Acetyl CoA moves into cytosol from mitochondria. It does not cross membranes, so must combine with oxaloacetate to give citrate. Once it has crossed the mitochondrial membrane, the citrate dissociates.
4) Acetyl CoA is converted to malonyl CoA. The enzyme for this step is acetyl CoA carboxylase. Malonyl CoA inhibits carnitine transferase, which prevents the FA entering the mitochondria for oxidation.
5) Malonyl is added to the growing chain. In each step, 3C are added and 1C is removed.
Give two ways in which insulin increases fatty acid synthesis
Activates pyruvate dehydrogenase (for pyruvate-> acetyl CoA)
Activates acetyl CoA carboxylase (for acetyl CoA-> malonyl CoA)
Outline the general structure of a lipoprotein.
Inner core= TAGs + cholesterol esters.
Outer shell= single layer of phospholipids + cholesterol + apoproteins.
Why does the liver need cholesterol?
Liver needs cholesterol to synthesise bile acids and steroid hormones.
How do statins lower blood cholesterol?
One type inhibits HMG-CoA reductase, therefore inhibiting synthesis of cholesterol.
Why might a gall bladder be removed and what happens when a gall bladder is removed?
Gallstones
Inflammation of the gall bladder (usually due to the stones)
up to 40% less dietary lipid
Which is then lost in feces due to a reduced capacity to absorb fats. The bile is less concentrated coming straight from the liver
Fat may not be broken down as effectively.
Define FatMax
the exercise intensity at which maximal fat oxidation is observed
Which intensity of exercise is fat the predominant fuel? A) Low B) Medium C) High D) Anaerobic
A) Low
What does the relative contribution of the type of fat utilised switch from & too?
Triacylglycerol (Intramuscular) –> Plasma FA (adipose)
Give three factors affecting fatmax
Training status
Gender
Type of exercise
Intensity
What emulsifies lipids
Bile salts
Fatty acid + monoglyceride = ?
Micelle
Where do chylomicrons travel
Around the body in the bloodstream
Define postprandial
After a meal
Which vein are chylomicrons secreted into:
a. vagus
b. carotid
c. lymphatic
d. subclavian
d. subclavian