Chapter 4: Lipids Flashcards
lipids contain?
carbon, hydrogen, oxygen
*it has less/more oxygen in proportion with carbon and hydrogen
less
neutral fats
simple lipids
neutral fats with some other components
compound lipids
neutral fats containing phosphoric acid and nitrogenous base
ex: sphingomyelin, lecithin, and cephalin
phospholipid
are composed of fatty acid, nitrogen, and carbohydrate
ex: cerebrosides and gangliosides in the brain tissue
glycolipids
glycolipids
refers to complexes of lipid with protein
lipid + protein
lipoprotein
glycolipids
pertain to carbohydrate-containing lipids
cho + lipid
mucolipids
acids that occur in a natural triglyceride
fatty acids
lipid substances that contain sterols
exL cholesterol, steroid hormones, vitamin d, and bile salts
steroids
structure of lipids
3 fatty acids attached to a (1) glycerol molecule
fatty acids: classification -
degree of saturation is composed of
saturated and unsaturated fatty acids
no double bonds
each carbon atom has 2 hydrogen atom attached to it
saturated fatty acid
2 prevalent saturated fatty acids that can be seen in animal fats, butter, cheese, coconut oil, and chocolate
palmitic and stearic
has 1 double bond
monounsaturated fatty acids
has more than 2 double bonds
polyunsaturated fatty acids
refers to fatty acids with double bond
some carbon atoms are bound to a single hydrogen atom
unsaturated fatty acids
unsaturated fatty acids (4)
oleic, linoleic, linolenic, arachidonic acids
pertains to fatty acids with one double bond
ex: oleic acid
monounsaturated fatty acids
are fatty acids with 2 or more double bond
ex: linoleic acid
polyunsaturated fatty acids
fatty acids: chain length -
fatty acids composed of four or less carbon atoms
ex: acetate, butyrate, and propionate
short chain
fatty acids: chain length -
fatty acids composed of 6-12 carbons
do not need special transport system
ex: caproic, caprylic, capric, and lauric to the liver and into the mitochondria for oxidation
medium chain
fatty acids: chain length -
composed of 14 carbons or more and needs transporters to enter the mitochondrium
ex: pamitic, mystiric, and stearic acids
long chain
fatty acids: essentiality
classifies into
linoleic and linolenic
fatty acids: essentiality
omega 6
linoleic
fatty acids: essentiality
omega 3
linolenic
fatty acids: essentiality
fatty acid is a derivative of arachidonic fatty acid
promotes arterial dilatation and contractility of the heart
linoleic
fatty acids: essentiality
fatty acid is a derivative of eicosanoids like the eicosapentanoic acid (epa) and docosahexanoic acid (dha)
promotes growth and development, and modulates clotting and blood pressure
linolenic
are derivatives of the 20 carbon
includes thromboxane and leukotrienes
eicosanoids
contains 20 carbons with 5 double bonds
eicosapentanoic acid (epa)
contains 20 carbons with 6 double bonds
docosahexanoic acid (dha)
properties of fats
effects of heat include formation of a pungent odor and _____ formation upon exposure to excessive heat
acrolein
properties of fats
refers to the unpleasant change in colors, tastes, and odors due to the oxidation of fats and formation of acrolein
rancidity
a by-product of oxidative process (rancidity), is responsible for this rancid taste
butyric acid
formation of insoluble soaps in the intestinal tract
saponification
refers to the process of adding hydrogen to double bonds to increase the degree of saturation
hydrogenation
hydrogenation - structure of cis and trans fatty acids
are hydrogens next to the double bond wherein hydrogen atoms are on the same side of the carbon chain
found in most fats
cis fatty acids
hydrogenation - structure of cis and trans fatty acids
refer to hydrogens next to the double bond wherein hydrogen atoms are on the opposite side of the carbon chain
ex: milk and butter, may behave like saturated fatty acid
trans fatty acids
hydrogenation - types
cis to trans form
ex: vegetable oil spreadable
partial hydrogenation
hydrogenation - types
make pie crust flaky and puddings creamy
complete hydrogenation
process of dispersing fat globules onto another liquid to become miscible
emulsification
fats - function
storage form of energy, 1 g of fat provides # kcal and # kJ
9 kcal or 37.8 kJ
fats - function
transporter of fat
soluble vitamins
a, d, e, k
fats - function
sources of essential fatty acids
linoleic and linolenic acids
fats - function
thermal insulation
this maintains body temperature within the normal range for necessity of life
adipose tissue or body fat
normal body temp (C/F)
37-37.5 C
98.6 F
important constituent of tissue structure
T/F essential precursor substances - lipids serves as components of materials required for metabolic functions and tissue integrity
T
important constituent of tissue structure
survival - females need _____%, males need _____%
12%; 3%
important constituent of tissue structure
T/F reproduction - amount of fats in the body dictate the success of ovulation, pregnancy, and lactation
T
important constituent of tissue structure
membrane function - component of membrane _____ of cells; can regulate the conformation of proteins and thereby regulate the membrane-barrier function
lipid bilayers
important constituent of tissue structure
serves as precursors of eicosanoids - _____ and other lipid substances; these are substances with hormone-like effects that exert a profound influence on many cellular reactions
prostaglandins
important constituent of tissue structure
sterols - like _____ aid emulsification of fats
bile acids
important constituent of tissue structure
sterols - _____ as precursor of vitamin d
cholesterol
fats - steps of digestive process
- bulk of chemical digestion of fat takes place in?
small intestine
fats - steps of digestive process
- the presence of fat stimulates secretion of the hormone _____ that contracts the gall bladder to release _____
cholecystokinin; bile salts
fats - steps of digestive process
- bile salts make fat increased area for the action of _____
the protein _____ enables the reaction to take place
lipase; colipase
fats - steps of digestive process
- _____ that are released into the small intestine contain the enzyme pancreatic lipase or steapsin (which breaks down triglycerides into its component glycerol and fatty acids), cholesterol esterase (forms cholesterol esters by attaching free cholesterol to fatty acids, needed for the absorption of cholesterol), and intestinal lecithinase that breaks down lecithin
pancreatic secretions
fats - steps of digestive process
- pancreatic secretions that are released into the small intestine contain the enzyme _____ or _____ (which breaks down triglycerides into its component glycerol and fatty acids), cholesterol esterase (forms cholesterol esters by attaching free cholesterol to fatty acids, needed for the absorption of cholesterol), and intestinal lecithinase that breaks down lecithin
pancreatic lipase or steapsin
fats - steps of digestive process
- pancreatic secretions that are released into the small intestine contain the enzyme pancreatic lipase or steapsin (which breaks down triglycerides into its component glycerol and fatty acids), _____ (forms cholesterol esters by attaching free cholesterol to fatty acids, needed for the absorption of cholesterol), and intestinal lecithinase that breaks down lecithin
cholesterol esterase
fats - steps of digestive process
4.. pancreatic secretions that are released into the small intestine contain the enzyme pancreatic lipase or steapsin (which breaks down triglycerides into its component glycerol and fatty acids), cholesterol esterase (forms cholesterol esters by attaching free cholesterol to fatty acids, needed for the absorption of cholesterol), and _____ that breaks down lecithin
intestinal lecithinase
fats - steps of digestive process
- end products of digestion are (4)
fatty acids, glycerol, monoglycerols, and diglycerols
fat absorption - steps
a. formation of _____
micelles
fat absorption
b. entry of micelles into the _____
brush border of the intestine
fat absorption
c. release of _____
lipids
fat absorption
d. reabsorption of _____ into the blood
bile
fat absorption
e. resynthesis of _____
fatty acids
fat absorption
f. absorption into the _____ system
lymphatic system
fat absorption
g. formation of the _____ complex
lipoprotein
it is recyclable; synthesized in the liver; stored in the gallbladder and reabsorbed in the blood if not excreted in the colon
bile
bile is synthesized in the
liver
bile is stored in the
gallbladder
are the transport vehicles for lipids in the lymph or blood
lipoproteins
lipoproteins classification based on its hydrated density
made up of triglycerides and transports lipids from the intestine to the liver
chylomicrons
lipoproteins classification based on its hydrated density
is formed in the liver; largely made up of triglyceride
very low-density lipoprotein (VLDL)
very low-density lipoprotein, low-density lipoprotein, and high-density lipoprotein is formed in the
liver
lipoproteins classification based on its hydrated density
formed in the liver and is largely made out of cholesterol
low-density lipoprotein (LDL)
very low-density lipoprotein is made up of
triglyceride
low-density lipoprotein is made up of
cholesterol
lipoproteins classification based on its hydrated density
refers to the intermediate between VLDL and LDL
intermediate-density lipoprotein (IDL)
lipoproteins classification based on its hydrated density
is formed in the liver and made up of proteins
high-density lipoproteins (HDL)
high-density lipoproteins is made up of
proteins
VLDL, IDL, and LDL carry cholesterol TO the cells for _____
utilization
HDL carries cholesterol FROM the cells to the liver for _____ for the body
breakdown and elimination
accumulation of cellular cholesteryl esters is prevented by:
suppress the synthesis of LDL receptor, thus decreasing the rate of low-density accumulation by endocytosis
high intracellular levels of cholesterol
accumulation of cellular cholesteryl esters is prevented by:
suppress the synthesis of LDL receptor, thus decreasing the rate of low-density accumulation by _____
endocytosis
accumulation of cellular cholesteryl esters is prevented by:
inhibits the biosynthesis of cholesterol
excess intracellular cholesterol
fat metabolism
- synthesis of triglycerides from the abundance of _____ and _____ takes place in the liver and adipose tissues with the aid of lipoprotein lipase and insulin
glucose and fatty acids
1 synthesis of triglycerides from the abundance of glucose and fatty acids takes place in the _____ and _____ with the aid of lipoprotein lipase and insulin
fat metabolism
liver and adipose tissues
fat metabolism
- oxidation of fatty acids for energy using lipase of _____ and make fatty acids available sources of energy
lipolysis
fat metabolism
- synthesis of triglycerides from the abundance of glucose and fatty acids takes place in the liver and adipose tissues with the aid of _____ and _____
lipoprotein lipase and insulin
fat metabolism
- synthesis of glucose from _____ if there is an inadequate glucose
glycerol
fat metabolism
- formation of _____ when glucose is lacking and there is a need for energy
ketone bodies
fat metabolism
- _____ substrate
energy
fat metabolism
- synthesis of _____ and _____
bile and cholesterol
fat metabolism
- synthesis of _____ and other biologically important substances
steroid hormones
fat metabolism
- synthesis of _____
lipoproteins
fats - recommended intake
should constitute _____ of the total requirement for all age groups
15-30%
fats - recommended intake
for infants
30-40%
fats - recommended intake
lower limit for adults is _____% to promote absorption of vitamin a
15%
fats - recommended intake
recommended by most dietary guidelines as a preventive measure against the risk of cardiovascular and other degenerative disease
upper limit
fats - recommended intake
pufa should constitute _____ of the total energy requirement
10%
fats - recommended intake
mufa should constitute ____
10-15%
fats - recommended intake
sfa should constitute
7-10%
food sources
composed of
vegetable oils and animal fats
food sources
almond, canola oil, cashews, olive oil, olives, peanut oil, etc.
vegetable oils
food sources
animal meats, beef tallow, poultry, etc.
animal fats
lipids - health effects
associated with cancer, but has no clear and direct relationship established.
some studies show that fats do not initiate cancer but may have a role in promotion of carcinogens
-
lipids - health effects
cardiovascular diseases -
it have been implicated because of their susceptibility to oxidation
pufa
lipids - health effects
cardiovascular diseases -
______ and _____ have been implicated because of their ability to cause hypercholesterolemia
sfa and cholesterol
2 atherogenic factors
hypercholesterolemia and oxidation
lipids - health effects
behave like saturated fatty acids
trans fats
is the process of forming plaques in the intima layer of arteries
Atherogenesis
increased levels of LDL, IDL, and VLDL and low levels of HDL characterize _____
cardiovascular disease
good cholesterol
high density lipoprotein (HDL)
bad cholesterol
low density lipoprotein (LDL)
essential fatty acid deficiency
symptoms od deficiency in animals:
depressed growth, scaly dermatoses, and increased permeability of the skin, fatty liver, kidney damage, and impaired reproduction
linoleic acid (n-6 pufa)
essential fatty acid deficiency - linolenic acid (n-3 pufa)
derivatives of linolenic acid (2) that have their own specialized distinct functions in the retina and central nervous system
eicosapantaenoic acid (epa) and docosahexanoic acid
essential fatty acid deficiency - linolenic acid (n-3 pufa)
eicosapantaenoic acid (epa) and docosahexanoic acid have their own specialized distinct functions in the (2)
retina and central nervous system
essential fatty acid deficiency
deficiency in the nerve tissue: altered retinal function, decreased visual activity, and impaired learning ability in animals
linolenic acid (n-3 pufa)
ratio of omega 3: omega 6 fatty acids that may produce health benefits
1:5 or 1:10
weight control - fats can easily cause weight gain due to
high kcal value
9 kcal/g
weight control - fats can easily cause weight gain due to
low satiety - high fat intake causes a decrease of _____ that caused increased appetite and low acitivity
leptin level
weight control - fats can easily cause weight gain due to
efficient metabolism - after weight loss, there is increased _____ that enables you to store more fats
lipoprotein lipase
weight control - fats can easily cause weight gain due to
gallbladder disease - decreased fat intake may cause poor _____
gallbladder movement
weight control - fats can easily cause weight gain due to
gallbladder disease - increased fat intake may increase _____
cholesterol deposition
fat: issues
can cause gastrointestinal upsets, decal urgency, anal leakage, and displacement of fat-soluble vitamins (can be fat-based, synthetic, combination fat replacers)
ex: olestra and oatrim
fat replacers