Lesson 5 Flashcards
why are lipids necessary (3)
enhance flavor
increase absorption of fat-soluble vitamins and phytochemicals
contribute to satiety
how much fat do we need to properly absorb fat soluble vitamins ?
20g fat
what is fat ? what kind of tissue
fat is a connective tissue which supports other tissues
what does visceral fat do ?
a fatty apron, covers and protects abdominal organs
what does subcutaneous fat do ?
helps maintain body heat and cushions the body
too much ____ fat increases chances of CVD
visceral
fat provides more than __ the amount of energy of carbs and protein
twice
what is the only form of energy stored for prolonged periods of time
fat
what energy do we use when we are at rest
fat
why is fat a better storage for than glycogen ?
because glycogen is too bulky and branched
what is the downside to fat storage ?
we can store an unlimited amount and fat cells can enlarge to 1000x their original size
what are the 4 main types of lipids ?
fatty acids
TG
phospholipids
cholesterol
what are fatty acids made of ?
chain of carbon atoms attached to hydrogen atoms , with a methyl group at one end and an acid group at another
what are triglycerides made of?
made of 3 fatty acid chains and a glycerol
what are phospholipids made of ?
2 fatty acids
how many fatty acids does cholesterol have ?
none
why is cholesterol structure special ?
does not contain fatty acids
short chain fatty acids are how long ?
2-4 C
medium chain fatty acids are how long ?
6-12C
long chain fatty acids are how long ?
14-24 C
what kind of fatty acid is acetic acid ?
short chain (2C)
what are the two fatty acid configurations ?
saturated (with hydrogen) (no double bonds)
unsaturated (double bonds causing kink in chain)
what are the two kinds of unsaturated fatty acids, depending on amount of double bonds ?
monounsaturated and polyunsaturated
what determines the behavior of the lipid ?
saturation level
what are oils ?
lipids that are liquid at room temperature
what are oils predominantly composed of ?
unsaturated fatty acids
why is duck fat more solid than oil?
half the amount of saturated fatty acids, therefore between solid and liquid
what is considered the end of the fatty acid molecule
the carbon atom of the methyl group
what is another name for the carbon on the methyl group of the FA
the omega (w) end
if an 18 C fatty acid has two double bonds, the first of which from the methyl end is on the 6th carbon, then what is the name of that FA ?
18,2, w6
FA with 18C, 1 double bond from methyl end on 9th carbon, what is its name ?
18,1,w9
what is the word for omega 3 ?
alpha linolenic acid
what is the word for omega 6 ?
linoleic acid
why are w3 and w6 so important ?
the body cannot make double bonds in this particular position, therefore they are essential nutrients
is it easy to get w6?
yes
is it easy to get w3 ?
yes
what happens to w6 in the body ?
follows arachidonic acid pathway, crucial for synthesis of cell membranes
what happens to w3 in the body ?
becomes DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid)
what does DHA (docosahexaenoic acid) do ?
important for brain function and growth in infant as well as maintenance of brain function in adults
a deficit in DHA is associated with what
impaired learning