MACRONUTRIENTS: LIPIDS Flashcards
what are the 3 lipid groups
- simple (neutral fats)
- compound
- derived
simple lipids consists primarily of what?
triacylglycerols (TAG)
what are adipocytes?
fat cells
why does triacylglycerol synthesis increase after a meal?
- food absorption increase blood levels of fatty acids and glucose
- relatively high levels of circulating insulin facilitate triacylgylcerol synthesis
what is lipolysis
triacylglycerol catabolism
what are the 4 conditions that lead to the mobilization of fatty acids via lipolysis
- low-moderate intensity exercise
- low-calorie dieting or fasting
- cold stress
- prolonged exercise that depletes glycogen reserves
what are the health concerns associated with trans fatty acids?
- increases harmful low-density lipoprotein cholesterol (LDL)
- decreases beneficial high-density lipoprotein cholesterol (HDL)
what is a phospholipid?
fatty acid joined to phosphate group and nitrogen-containing molecule
what are the 4 main functions of phospholipids?
- interacting with water and lipid to modulate fluid movement across cell membrane
- maintain structure of cell
- blood clotting
- provide structure to insulating sheath that surrounds nerve fibre
what are glycolipids?
fatty acids bound with CHO and N2
what are lipoproteins?
protein molecule joined with a triacylglycerol or phospholipid
list 3 compound lipids
- phospholipids
- glycolipids
- lipoproteins
what are the 4 types of lipoproteins?
- chylomicrons
- high-density lipoprotein (HDL)
- very low-density lipoprotein (VLDL)
- Low-density lipoprotein (LDL)
What is the difference between HDL and LDL
HDL: protects against heart disease
LDL: facilitates heart disease
what is the best known derived lipid?
cholesterol
what is cholesterol?
exists only in animal tissue
does not contain fatty acids
shares some of lipids’ phys and chem characteristics
what are the 4 major functions of lipids?
- energy source and reserve
- protect vital organs
- thermal insulation
- vitamin carrier and hunger suppressor
why is fat an ideal source of cellular fuel?
- carries a lot of energy per unit weight
- transports and stores easily
- ready source of energy
what is the term for the catabolism of triacylglycerol?
lypolysis
what are the three sources of energy from fat?
- triacyclglycerol in fat cells (adipocytes)
- intramuscular triacylglycerol
- circulating triacylclycerol in lipoprotein complexes
what are two catacholamines that stimulate lipid activation
- epinephrine
2. norepinephrine
