Fats as fuels Flashcards
(19 cards)
What are fatty acid tails useful for?
They can be oxidised- releasing lots of energy
C1
Formic acid
C2
Acetic acid
C3
Propionic acid
C4
Butyric acid
C16
Palmatic acid
C18
Stearic acid
C20
Arachidic acid
TRANS FATS
Main trans fat is Elaidiac acid —> found in partially hydrogenated vegetable oils
Chemically modified from cis to trans
This changes the reactivity and the membranes
UNSATURATED
eg Oleic Acid
SATURATED
found in animal fats
NO C=C
Roles of lipids
Components of cell membranes- phospholipids and cholesterol
Precursors of hormones
- cholesterol–> steroid hormones
- arachidonic acid —> prostaglandins
Long terms fuels —-> ENERGY
1G fat - 38 KJ
– Stored in large fat droplets in fat cells of adipose tissue
The membranes of the fat droplets are stiff as there are forces between the tails
What is the significance of the “kinks”
Decrease the stiffness as the fatty acid are brought apart
This results in the membranes being flexible
Describe the breakdown of the stored triglyceride fat- adipose tissue
Adrenaline or glucagon activates the breakdown of triaglycerol —> Diaglycerol—> mono glycerol —-> glycerol
fatty acids are cleaved- and travel in the plasma, bound to albumin, acting as duels for muscle heart liver
FORM FADH2 and NADH
glycerol diffuses to the bloodstream to all tissues
What converts triaglycerol to diaglycerol
triaglycerol lipase
What converts diaglycerol to mono glycerol
DAG lipase
What converts monoglycerol to glycerol
MAG lipase
Describe glycerol uptake
Since glycerol is water soluble- it is taken up by all tissues
MOST TISSUES: Enters glycolysis pathway
converts to pyruvate where its oxidised to pyruvate
IN LIVER IN STARVATION : Enters glycolysis and can be converted to glucose by gluconeogenesis
Fatty acid Metabolism
Beta oxidation pathway
All reactions occur in the mitochondrial matrix
Intermediates present as CoA thioesters
Biological energy of fatty acid molecule- transferred to 2H atoms (
