Biochemistry I Exam 3 (hunterschaff)
What is the active form of vitamin D in the kidneys?
1,25-hydroxy vitamin D3 calcitriol
What are the two components of glycosphingolipids?
1-10 sugars and ceramide
Describe lipid absorption & transport
1. broken down in to micelles 2. micelles absorbed by passive diffusion into SI 3. reesterfied into TAGs and enters smooth er 4. packaged into chylomicron in golgi complex
What mass of bile salts are secreted daily?
15-30 g
What is the omega numbering for oleic acid?
18:1ω9
What is the delta numbering for oleic acid?
18:1∆9
What is the omega numbering for linoleic acid?
18:2ω6
What is the delta numbering for linoleic acid?
18:2∆9,12
What is the omega numbering for α-linolenic acid (ALA)?
18:3ω3
What is the delta numbering for α-linolenic acid (ALA)?
18:3∆9,12,15
Our body can't add a double bond from n-_ to n-_.
1; 7
Know the precursors for each eicosanoid series (2 series, 3 series, etc.).
2 & 4 series: aracadonic acid (ARA) 3 & 5 series: eicosapentaenoic acid (EPA)
Which eicosanoids are responsible for inflammation?
2 series prostaglandin (PG) & thromboxanes (TX) and 4 series Leukotrienes (LT)
What does phosphatidylserine signal to when it moves to the outer leaflet?
WBC for apoptosis
Which compound does esterase NOT digest? a. Cholesterol ester b. Free cholesterol c. Vitamin A d. Vitamin E
a. Cholesterol ester
What is the fate of peptide hormone digestion? a. Denatured b. Not denatured
a. Denatured
Are growth hormones peptide hormones or steroid hormones? a. Peptide b. Steroid
a. Peptide
Which is TRUE of cholesterol? a. it has a hydroxyl on carbon-3 b. it is transported in blood by albumin c. in the serum, it is eliminated by the kidneys d. it is present in prokaryotic membranes
a. it has a hydroxyl on carbon-3
What two molecules are important in endogenous cholesterol synthesis?
acetyl CoA and CoQ10
What group does platelet activating factor (PAF) have at sn-2?
acetyl group
What are fatty acids also called?
acyls
What are free fatty acids in plasma bound to in transport?
albumin
What essential nutrient is technically not a vitamin, but similar to water-soluble vitamins?
choline
What is used in lecithin, sphingomyelin, and acetylcholine?
choline
What lipoprotein is exogenous only?
chylomicron
Where are micelles packaged into in the enterocyte?
chylomicron in golgi complex
What are some sources of exogenous cholesterol? How much do we get per day?
chylomicron remnants from animal products; we get approximately 1 g/day
What lipoproteins are mostly triglycerides?
chylomicrons and VLDL
How are TGs transported following absorption?
chylomicrons and VLDLs
Where is each lipoprotein synthesized?
chylomicrons: enterocyte of SI VLDL: liver LDL: from VLDL HDL: SI and Liver
What percentage of coconut oil is saturated, and how does this compare to butter or beef?
coconut oil is 90% compared to butter (64%) and beef (40%)
What are 3 catalyzers of oxidation?
enzymes (e.g. lipoxygenase and myeloperoxidase), metals (e.g. Fe, Cu, and Co), and UV light
What are functions of the ester & ether phospholipids?
ester: released from white blood cells during inflammation, allergy and injury, and stimulates platelet aggregation (clotting) ether: plasmalogen - concentrated in brain, heart, nerve & muscle
What enzyme removes FA on cholesterol and vitamins A & E
esterase
Where is cardiolipin found in vivo?
exclusively in the inner mitochondrial membrane
How is the bile that is not part of micelles absorbed in the ileum?
facilitated diffusion into the enterocyte and taken back to the liver via the portal vein
What vitamins do micelles contain?
fat-soluble vitamins (ADEK)
What type of lipids are solid at room temperature?
fats
What are micelles made up of?
fatty acids, monoglycerides, fat-soluble vitamins, cholesterol, and bile salts
What is the only mechanism for cholesterol excretion?
feces
What will 2 series prostaglandins (PG) and thromboxanes (TX) affect?
inflammatory and clotters
In cell membrane signaling, phospholipase C digests the ______ head group from ______________ (__) leaving a __.
inositol; phosphatidylinositol (PI); DG
What is the structure of a fatty acid?
ionized carboxylic acid and hydrocarbon chain
What does methylene interruption allow, and why?
it allows a more flexible structure because it can rotate around the methylene in the middle to several conformations
What issues are associated with an accumulation of ceramide?
joint deformity
What is the most common phospholipid in the body?
lecithin
What determines the lung maturity of a fetus?
lecithin:sphingomyelin ratio (L/S)
What percentage of fatty acids are found free in plasma?
less than 10%
What fatty acids are found in myelin sheath sphingomyelin?
lignoceric acid and nervonic acid
How is lipid malabsorption treated?
limit fat intake and supplement with pancreatic lipase and/or bile salts
What enzyme for lipid digestion is released in the mouth?
lingual lipase
What enzyme removes sn-3 on TG containing short or medium chain FA?
lingual lipase
What is the common name for the fatty acid with the delta numbering 18:2∆9,12?
linoleic acid
What are chylomicros, very low density lipoprotein (VLDL), low density lipoprotein (LDL), and high density lipoprotein (HDL) examples of?
lipoproteins (lipid transport molecules)
What must cholesterol esters be transported by?
lipoproteins or in bile
What eicosanoid enzyme does not change the number of double bonds?
lipoxygenase (LOX)
What will 3 series prostaglandins (PG) and thromboxanes (TX) affect?
little to no effect
What will 5 series leuktrienes (LT) affect?
little to no effect
Where is bile made?
liver
Where is cholesterol regulated?
liver
Where does endogenous cholesterol synthesis occur?
liver and intestines
Where is cholesterol synthesized?
liver, small intestine, and specialized tissue
What type of lipid is myristic acid?
long chain saturated fatty acid
What type of lipid is palmitic acid?
long chain saturated fatty acid
What diet ratio of n-6 to n-3 would decrease risk of CVD?
lowering from 7-15:1 to 3:1
Which hydrogen is most likely to be attacked in a PUFA?
lowest number/lowest strength hydrogen or methylene interruption
Where are bile acids made and from what molecule?
made in liver from cholesterol
Where is bile made, stored & secreted into?
made in liver, stored in gall bladder and secreted into small intestine (duodenum) and 95% reabosorbed in the ileum; 5% that is not reabsorbed ends up in the feces
What are most fatty acids in coconut oil?
medium chain (mostly lauric acid)
What are the beneficial biological implications of oxidation?
metabolism, cell signaling, and kills bacteria
Which end of the FA does ω start from?
methyl
What do the parts of digested lipids coalesce in?
micelles with bile acids
What are many genetic diseases due to?
missing or malformed enzymes, specifically degradation enzymes allowing compounds to accumulate causing damage
Where is phosphatidylethanolamine highly concentrated?
mitochondrial membranes
What is another term for monoglyceride (MGs)?
monoacylglycerols (MAGs)
What type of sugar molecule does galactocerebroside contain?
monosaccharides
What type of sugar molecule does glucocerebroside contain?
monosaccharides
Where is phosphatidylserine found in high concentrations?
myelin
What needs to occur to lipids in order to allow digestion in stomach?
need to be emulsified
What issue is associated with an accumulation of sphingomyelin?
neurodegeneration
What is the genetic sphingomyelinase deficiency that results in sphingomyelin accumulation causing mental retardation?
niemann-pick
What is an example of reactive nitrogen species (RNS) radical?
nitric oxide (•NO)
Are cholesterol esters more polar than free esters?
no
Do brushborder lipases exist?
no
Do lipids have a low satiety value?
no
Does coconut oil decrease HDL?
no
Does coconut oil decrease LDL?
no
Does lipid digestion occur in the LI?
no
Is an AOX overdose expected with consumption of whole fruits & vegetables?
no
Is conversion of alpha-linolenic acid to EPA and DHA efficient?
no
Is glucocerebroside found in neural tissue?
no
Is linoleic acid bioactive?
no
Is n-6:n-3 ratio as important to SFA:UFA ratio?
no
Is phophatidyl serine normally found on the outer leaflet of the plasma membrane?
no
Is α-linolenic acid (ALA) bioactive?
no
How does consumption of cholesterol (from 100-900mg/day) affect LDL cholesterol levels?
no affect
Have AOX supplements been shown to be effective at helping treat cancer?
no, except for bladder cancer (RR 1.52; 95% CI 1.06-2.17)
Is overdosing on fruits and veggies easy?
no, it is extremely difficult
What type of antioxidant (AOX) are H donors?
nonenzymatic AOX
What type of antioxidant (AOX) are metal binders?
nonenzymatic AOX
What type of antioxidant (AOX) are oxygen scavengers?
nonenzymatic AOX
What type of antioxidant (AOX) are singlet oxygen quenchers?
nonenzymatic AOX
What type of sugar molecule does ganglioside contain?
oligosaccharides (3-10 sugars)
What are the essential fatty acids?
omega-6 (n-6) and omega-3 (n-3) fatty acids
Which has a higher omega-3 fatty acid content per ounce: organic milk or conventional milk?
organic milk (but not by much)
What is the fate of TG in the liver?
packed into very low-density lipoprotein (VLDL) and sent into circulation
What is the common name for the fatty acid with the numbering 16:0?
palmitic acid
What is the main fatty acid we produce in the liver?
palmitic acid
What organ does secretin cause to contract?
pancreas
Which organs does CCK cause to contract?
pancreas and gallbladder
What enzyme removes sn-1 and sn-3 FA on TG and DG?
pancreatic lipase
What lipases digest ~80% of triglycerides (TGs)?
pancreatic lipases
Where are phospholipases found?
part of digestion and in toxins and venoms
How are micelles absorbed in the duodenum and jejunum (SI)?
passive diffusion
Which patients could benefit from omega-3 fatty acids?
patients with ADHD (EPA only), bipolar disorder, depression (>60% EPA), hypertension, osteoarthritis, pregnant (decrease preterm birth), premature infants, and rheumatoid arthritis (>2.7 g/d)
What are the 3 parts of a phospholipid structure?
peripheral protein, integral protein, and single layer of phospholipids
During cellular oxidative damage, bonds rearrange and oxygen is easily added to a lipid forming what?
peroxide
What glycerophospholipid contains palmitic acid, oleic acid, and choline?
phosphatidylcholine (lecithin)
What makes up 50% of all of the phospholipids in the human body?
phosphatidylcholine (lecithin)
What glycerophospholipid contains stearic acid, ARA, and ethanolamine?
phosphatidylethanolamine
What glycerophospholipid often contains n-3 & n-6 at sn-2?
phosphatidylethanolamine
What makes up 20% of the body's phospholipids?
phosphatidylethanolamine
What makes up 45% of the brain's phospholipids?
phosphatidylethanolamine
What glycerophospholipid contains palmitic acid, oleic acid, and glycerol?
phosphatidylglycerol
What glycerophospholipid is mostly found in lung surfactant or mitochondria?
phosphatidylglycerol
What is the precursor to cardiolipin?
phosphatidylglycerol
What makes up 1-2% of the body's phospholipids?
phosphatidylglycerol
Which phospholipid is important for membrane anchoring?
phosphatidylinositol
Which phospholipid is important in covalent modification of enzymes?
phosphatidylinositol
What glycerophospholipid contains stearic acid, ARA, and inositol?
phosphatidylinositol (PI)
What glycerophospholipid is important in cell signaling (involved in covalent modification process)?
phosphatidylinositol (PI)
What makes up 10% of the brain's phospholipids?
phosphatidylinositol (PI)
What glycerophospholipid contains stearic acid, ARA, and serine?
phosphatidylserine
What glycerophospholipid has the highest concentration of n-3 and n-6 than any other phosopholipid?
phosphatidylserine
What glycerophospholipid is important in regulating phagocytosis?
phosphatidylserine
What glycerophospholipid is mostly found in myelin?
phosphatidylserine
What makes up less than 10% of the body's phospholipids?
phosphatidylserine
Which glycerophospholipid contains n-3 & n-6?
phosphatidylserine
What enzyme removes sn-2 FA on phospholipids (mostly lecithin)?
phospholipase A2
Which enzyme releases arachidonic acid from membrane phospholipids? a. phospholipase A1 b. phospholipase A2 c. phospholipase C d. phospholipase D
phospholipase A2
What do bacteria produce to dissolve membranes and spread infection?
phospholipases
What part of the lipoprotein (lipid transport molecule) makes it water-soluble?
phospholipid exterior
What glycerophospholipid anchors protein to extracellular membrane?
phosphtidylinositol (PI)
What can be used to treat hypercholesterolemia, and why?
plant sterols, because they compete with cholesterol for absorption
What ether lipid is concentrated in the brain (50%), heart, nerves and muscles?
plasmalogen
A glycerophospholipid with an acetyl group on sn-2 is called what?
platelate activating factor (PAF)
What is produced by platelets and white blood cells causing inflammation, hypersensitivity reactions, free radical formation, and platelet aggregation?
platelet activating factor (PAF)
What in chyme acts as emulsifiers?
polysaccharides, phosopholipids, and digested proteins
What type of fatty acid has more than 1 double bond and is an oil at room temperature?
polyunsaturated fatty acid (PUFA)
What are omega-6 fatty acid's functions?
prevents water loss from skin, cell signaling, and blood clotting
What is needed to make pancreatic lipase functional?
procolipase, trypsin, enteropesidase, colipase, bile, and calcium
What are 5 groups of eicosanoids?
prostaglandins (PG), thromboxanes (TX), leukotrienes (LT), resolvins (Rv), and lipoxins (LX)
What are the 4 types of reactive species?
radical and nonradical reactive oxygen species (ROS) and radical and nonradical reactive nitrogen species (RNS)
What are the remaining 5% of lipids in our diet?
sterols (mainly cholesterol) and phospholipids
What is the fate of TG in adipose tissue?
stored in lipid droplets
What does trans packing allow for a lipid?
stuck in a linear position and acts like a saturated fat in the body, less fluff
What gives ganglioside its specificity?
sugar patterns
What are 2 examples of reactive oxygen species (ROS) radicals?
superoxide (O2•-) and hydroxyl (•OH)
What bile salt contains bile acid and taurine?
taurocholate
What is the form of vitamin D that is taken from food and supplements?
vitamin D3 (inactive) calciferol
What are the 3 fat-soluble H donors?
vitamin E, carotenoids, and coenzyme Q10
What does bile contain?
water, lecithin, bile salts, cholesterol esters, and bilirubin
When does toxicity of AOX become an issue?
when you start pulling out a single ingredient of fruits and veggies in doses you would not get in food
Are FA found in your membrane phospholipids directly related to your dietary habits?
yes
Are ROS/RNS involved in inflammation?
yes
Are cholesterol esters less polar than free cholesterol?
yes
Can triglycerides be a fat?
yes
Can triglycerides be an oil?
yes
Do lipids have a high satiety value?
yes
Does coconut oil increase HDL?
yes
Does coconut oil increase LDL?
yes
Is arachidonic acid (ARA) bioactive?
yes
Is docosahexaenoic acid bioactive?
yes
Is eicosapentaenoic acid (EPA) bioactive?
yes
Is galactocerebroside found in neural tissue?
yes
Is most plasma cholesterol esterified (not free)?
yes
Is n-3 an essential FA?
yes
Is phosphatidylethanolamine able to H bond?
yes
Is phosphatidylglycerol highly saturated?
yes
Is phosphatidylserine normally found on the inner leaflet of the plasma membrane?
yes
Have fruits/veggies been shown to be effective at helping treat obesity?
yes (RR 1.34; 95% CI 1.22-1.48)
Have fruits/veggies been shown to be effective at helping treat cancer?
yes, both together and alone
What mass of bile salts are lost in feces daily?
~0.5 g
What is the mass of new bile made daily?
~0.5 g (note that the same mass is lost in feces daily)
H2O2 + e- = __
•OH (hydroxyl radical)
What type of radiation is needed for vitamin D synthesis?
UVB
What is anything with cholate in the name?
bile acid
What is used in cholesterol treatment?
bile acid binders
What type of antioxidant (AOX) is catalase (CAT)?
enzymatic AOX
What type of antioxidant (AOX) is glutathione peroxidase (GPx)?
enzymatic AOX
What type of antioxidant (AOX) is superoxide dismutase (SOD)?
enzymatic AOX
What will 4 series leuktrienes (LT) affect?
inflammatory
What issues are associated with an accumulation of gangliosides?
blindness and muscle weakness
What is the precursor for bile?
cholesterol
What is the precursor for steroid hormones?
cholesterol
What is the precursor for vitamin D?
cholesterol
What is the storage form of cholesterol?
cholesterol esters
What are sterols that we get in our diet?
cholesterol, mostly as free cholesterol and 10-15% are cholesterol esters
What fatty acid does LOX produce 4 series leukotrienes (LT)?
ARA (n-6)
What is the average american mercury level?
0.19 µg/g of hair
What is the (possibly) inactive form of vitamin D found in the liver?
25-hydroxy vitamin D3 calcidiol
Where do we find lecithin in vivo?
45% of phospholipids in the brain, highly concentrated in mitochondrial membranes
What percentage of Calories swapped from SFA to PUFA will result in a decreased risk of CHD by 10%?
5% Calories swapped
How much time in the sun is needed for efficient weekly vitamin D synthesis?
5-15 minutes between 10 am and 3 pm, 2-3 times per week
What is the molecule in skin that interacts with UVB to initiate vitamin D synthesis?
7-dehydrocholesterol
What is the average american diet ratio of n-6 to n-3?
7:1 to 15:1
What is the composition of lung surfactant?
90% lipids, mostly lecithin, and 10% protein
What is a low mercury level?
<2.0 µg/g of hair
What is a high mercury level?
>2.0 µg/g of hair
Where do phospholipase A1, A2, C & D cleave on a phospholipid?
A1: sn-1 A2: sn-2 C: sn-3 D: sn-3
What does phosphatidylinositol (PI) contain at sn-2?
ARA
What fatty acid does COX produce 2 series prostaglandins (PG) and thromboxanes (TX)?
ARA (n-6)
What are the hormones that are released, decreasing gastric motility (gastric emptying), due to the presence of fat in the stomach?
CCK, GIP, and GLP-1
What issues are associated with an accumulation of cerebrosides?
CNS impairment
What fatty acid does COX produce 3 series prostaglandins (PG) and thromboxanes (TX)?
EPA (n-3)
What fatty acid does LOX produce 5 series leukotrienes (LT)?
EPA (n-3)
What are the products of esterase digestion?
FA & free compounds (cholesterol, vitamin A, and vitamin E)
What are the products of phospholipase A2 digestion?
FA & lysophospholipid
•OH + e- = __
H2O (water)
O2•- + e- = __
H2O2 (hydrogen peroxide)
What carries cholesterol from extrahepatic tissues to the liver?
HDL
What lipoprotein is mostly protein?
HDL
What is the rate limiting enzyme used in endogenous cholesterol synthesis?
HMG CoA reductase
What lecithin:sphingomyelin ratio (L/S) signifies that lungs are mature?
L/S > 2
What lipoprotein is mostly cholesterol?
LDL
What are the products of pancreatic lipase digestion?
MG and 2 FA
List enzymes, secretions & hormones involved in lipid digestion & where they are located
Mouth: Lingual Lipase [enzyme] Stomach: Gastric Lipase [enzyme]. CCK, GIP, GLP1 [hormones] Small Intestine: Bicarb [secretions] & Enzymes from Pancreas & Gallbladder. Bile Acids/Salts [secretions] from Gallbladder. Pancreatic Zymogens (procolipase, pancreatic lipase, prophospholipase) [inactive enzymes]. Pancreatic Lipase (Colipase, active pancreatic lipase, phospholipase A2, Esterase) [active enzymes]
Describe lipid digestion from mouth to excretion
Mouth: Lingual lipase released. Removes SN-3 on TG's. Containing short/medium chain FA. Produces Diglycerides (DG's) & FA's Stomach: Gastric lipases released. Removes SN-3 on TG's. Containing short/medium cahin FA. Produce Diglycerides & FA's Small Intestine: chyme enters releasing CCK & Secretin. CCK contracts the pancreas and gallbladder releasing bicarb & enzymes. Secretin contracts the pancreas releasing bicarb. Pancreatic Lipases (colipase, bile, calcium) remove the SN-1 & SN-3 on TG's & DG's. Produces Monoglycerides & 2 FA's Large Intestine: No digestion Remains excreted
O2 + e- = __
O2•- (superoxide)
What is the lipid core of a lipoprotein (lipid transport molecule) made up of?
TGs, cholesterol, and fat-soluble vitamins
What are some examples of steroid hormones?
androgens (testosterone), estrogens, progestagens (progesterone), glucocorticoids (cortisol), and mineralocorticoids (aldosterone)
What are some dietary sources for choline?
animal meats, dairy products, eggs, peanuts, broccoli, and soy
An increase in omega-3 eicosanoids will have what effect & why?
anti-inflammatory
What is the term for anything that can decrease oxidation by getting rid of free radicals or by other mechanisms?
antioxidants (AOX)
How do AOX work? What do they donate and from where?
antioxidants decrease the oxidation by getting rid of the free radicals or by other mechanisms; they donate a hydrogen normally from an OH group
What is the protein portion (enzymes, receptor ligands, etc.) of a lipoprotein (lipid transport molecule)?
apoprotein
What pharmacological treatment induces synthesis of anti-inflammatory eicosanoids?
asprin
Which patients have not shown a benefit from omega-3 fatty acids?
autism, cardiovascular disease, crohn's disease, and dementia
A high omega-6:omega-3 fatty acid ratio in the diet favors synthesis of which eicosanoid? a. 1 series PG b. 2 series PG c. 3 series TX d. 5 series LT
b. 2 series PG
What are the products of pancreatic lipase digestion? a. Glycerol & FA b. MG & FA c. DG & FA d. TG
b. MG & FA
What is the fate of steroid hormone digestion? a. Denatured b. Not denatured
b. Not denatured
Which of the following dietary lipids has the most influence on increasing blood cholesterol? a. Cholesterol b. Saturated fatty acids c. Monounsaturated fatty acids d. Polyunsaturated fatty acids
b. Saturated fatty acids
In which position would you find EPA? a. Sn-1 b. Sn-2 c. Sn-3 d. Sn-4
b. Sn-2
Which lipids are NOT charged at physiologic pH? a. glycerophospholipids b. cholesterol esters c. fatty acids d. sphingomyelins
b. cholesterol esters
If blood plasma levels are high in arachidonic acid, which supplement would be useful in increasing EPA & DHA? a. glucosamine & chondroitin b. cold water fish oil c. fat-soluble vitamins d. B-complex vitamins
b. cold water fish oil
How does cholesterol regulate HMG CoA reductase? a. covalent modification b. feedback inhibition c. positive effector d. enzyme induction
b. feedback inhibition
Which lipid is derived from arachidonic acid and works as a chemical messenger at or near production site? a. peptide hormone b. prostaglandin c. second messenger d. steroid hormone
b. prostaglandin
What are the benefits & hazards of ceramide?
benefits: regulates water permeability of skin (too much can cause cell death) hazards: can cause Farber (a joint deformity)
What contains water, lecithin, bile salts, cholesterol esters, and bilirubin?
bile
What organ is most resistant to dietary change?
brain
What are the products of lingual and gastric lipase digestion? a. Glycerol & FA b. MG & FA c. DG & FA d. TG
c. DG & FA
What activates trypsin? a. Dipeptidase b. Carboxypeptidase c. Enteropeptidase d. Lingual lipase
c. Enteropeptidase
Which molecule is NOT derived from cholesterol? a. vitamin D b. cortisol c. leukotriene A4 d. taurocholate
c. leukotriene A4
Which is the preferred PUFA source for the production of the 3 series prostaglandins? a. corn oil b. olive oil c. salmon oil d. flaxseed oil
c. salmon oil
What glycerophospholipid is found exclusively in the inner mitochondrial membrane?
cardiolipin (diphosphatidylglycerol)
What are the omega-3 fatty acid, docosahexaenoic acid's (DHA), functions?
cell signaling and important component of phospholipids in brain and retina
What are eicosanoids function?
cell signaling, gene expression, and inflammatory processes
An accumulation of what will cause Farber?
ceramide
What is important in cell signaling and regulation of cell death?
ceramide
What makes up ~50% of lipids in stratum corneum (outermost layer of epidermis)?
ceramide
What regulates water permeability of skin?
ceramide
What are some mechanisms used to increase surface area during digestion?
chewing, peristalsis, and emulsification
Who should limit albacore tuna to 6 oz./week?
children and pregnant/lactating women
What is a steroid alcohol?
cholesterol
What is found only in animal products?
cholesterol
What is required for cell membrane integrity?
cholesterol
Which enzyme is responsible for the cyclic pathway of eicosanoid formation? Which is responsible for the linear pathway?
cyclic pathway is COX and linear pathway is LOX
What eicosanoid enzyme removes 2 double bonds?
cycloxygenase (COX)
What type of enzyme is cholesterol 7-α-hydroxylase, and what is it used for?
cytochrome P450 enzyme and it is used to emulsify fats into cholic acid (cholate)
What disease is caused by a genetic defect in the enzyme sphingomyelinase leading to accumulation of sphingomyelin in the brain, liver & spleen? a. maple syrup urine disease b. sudden infant death syndrome (SIDS) c. Tay-Sachs disease d. Niemann-Pick disease
d. Niemann-Pick disease
Which of the following does not contain cholesterol? a. beef b. ham c. ice cream d. baked potato
d. baked potato
Why do triglycerides contain more energy per gram than carbs? a. they are more dense b. they are more hydrophobic c. they are in a more oxidized form d. they are in a more reduced form
d. they are in a more reduced form
What happens to lingual lipase activity with age?
decreases
What type of reaction occurs for triglycerides formation?
dehydration
How is omega-6 fatty acid, arachidonic acid (ARA), made?
desaturation (desaturase) of linoleic acid to γ-linolenic acid; elongation (elongase) of γ-linolenic acid to eicosatrienoic acid; desaturation of eicosatrienoic acid to arachidonic acid
What is another term for diglycerides (DGs)?
diacylglycerols
What are the major sources of liver cholesterol?
dietary cholesterol (chylomicron remnants), cholesterol from extrahepatic tissues (HDL), and de novo synthesis in the liver from carbs, lipids, and proteins
What are the products of lingual lipase digestion?
diglycerides and fatty acids
What are 20 C hormone-like compounds?
eicosanoid
How is omega-3 fatty acids, eicosapentanoic acid (EPA) and docosahexaenoic acid (DHA), made?
elongation and desaturation of only 5-9% α-linolenic acid (ALA) to eicosapentaonic acid (EPA); elongation and desaturation of eicosapentaonic acid (EPA) to docosahexaenoic acid (DHA)
Why is the surface area of lipids in the SI greatly increased?
emulsification using bile and peristalsis
What are bile salt's function?
emulsify large lipid droplets into micelles
What happens to the 5% of the bile that does not get efficiently reabsorbed in the ileum?
ends up in the feces
What are lipids digested to in the SI?
free fatty acids, sn-2 monoglycerides, cholesterol & lysophospholipids
Where are water-soluble H donors found in high concentrations?
fruits, veggies, whole grains, and legumes
Where are galactocerebroside & glucocerebroside found?
galactocerebroside is found in the neural tissue and glucocerebroside is found in non-nueral tissue
An accumulation of what will cause Krabbe?
galactocerebrosides
Where are bile acids stored?
gallbladder
Where is bile stored?
gallbladder
An accumulation of what will cause Sandhoff's?
gangliosides
An accumulation of what will cause Tay-Sachs?
gangliosides
How are gangliosides different from cerebrosides?
gangliosides contain oligosaccharides and cerebrosides contain monosaccharides
What enzyme for lipid digestion is released in the stomach?
gastric lipase
An accumulation of what will cause Gaucher?
glucocerebrosides
What is the backbone of glycerophospholipid?
glycerol
What makes up a glycerolipid?
glycerol backbone and fatty acid
What lipid contains a SFA at sn-1 and a UFA at sn-2?
glycerophospholipid
What contains bile salt, bile acid, and glycine?
glycocholate
What are the most common bile salts?
glycocholate (bile acid + glycine) and taurocholate (bile acid + taurine)
Which has a higher omega-3 fatty acid content per ounce: grass-fed beef or grain-fed beef?
grass-fed beef
What lipoprotein picks up free cholesterol from cells to take back to the liver?
high density lipoprotein (HDL)
In cell membrane signaling, a ______ binds to a receptor starting a cascade of signals that activate _________ _.
hormone; phospholipase C
What are the two parts of a phospholipid?
hydrophilic head and hydrophobic tail
What enzyme is used during vitamin D synthesis?
hydroxylase
Where is bile efficiently reabsorbed, and by what percentage?
ileum by 95%
What are some causes of lipid malabsorption?
impaired digestion or absorption; cystic fibrosis, bile acid insufficiency, celiac disease, Crohn's, etc.
What are the harmful biological implications of oxidation?
inactivate hormones, vitamin deficiencies, cell death, heart disease, cancer, and Alzheimer's disease
In what age group is lingual lipase most active?
infants
What can too much ceramide cause?
inflammation and cell death
An increase in omega-6 eicosanoids will have what effect?
inflammatory
What happens to micelles upon entering an enterocyte?
reesterified into TAGs, phospholipids, and cholesterol esters in smooth endoplasmic reticulum of enterocyte
What will insufficient lung surfactant cause in infants?
respiratory distress syndrome and death
Which has a higher omega-3 fatty acid content per ounce: grass-fed beef or salmon?
salmon
Where are the saturated & unsaturated FA found on glycerophospholipid's backbone?
saturated fat found at sn-1 and unsaturated fat found at sn-2
What are the major routes by which cholesterol leaves the liver?
secretion of VLDL, free cholesterol secreted in bile, and conversion to bile acids/salts
In cell membrane signaling, inositol releases _______ _______ from the __, ___ ______ activates ________ _____ _ (phosphorylating enzyme).
sequestered calcium; ER; Ca+ diglyceride; protein kinase C
What fish should you limit your consumption of due to mercury?
shark, swordfish, tilefish and mackerel
What lipids do not get absorbed by passive diffusion in the duodenum and jejunum (SI), and what happens to them?
short and medium chain FA pass directly into portal blood and taken to liver
The majority of lipids in nature are found as which lipid class?
simple
What are 2 examples of reactive oxygen species (ROS) nonradicals?
singlet oxygen (1O2) and hydrogen peroxide (H2O2)
Most lipid digestion occurs where, and due to which enzymes?
small intestine; due to colipase, active pancreatic lipase, phospholipase A2, & esterase
Where are MUFA & PUFA found on the TG?
sn-2
Which position contains the phosphate group in glycerophospholipid?
sn-3
An accumulation of what will cause Niemann-Pick?
sphingomyelin
What is in plasma membranes of all animal cells and highly concentrated in myelin sheaths of nerves?
sphingomyelin
What sphingophosphatide is made of sphingosine, fatty acid, phosphate, and choline?
sphingomyelin
What is an example of a sphingophospholipid? Where is it found?
sphingomyelin and it is found in plasma membranes of all animal cells highly concentrated in myelin sheath of nerves
Which enzymes are involved in sphingomyelin degradation?
sphingomyelinase and ceramidase
What is the backbone of sphingophospholipid?
sphingosine
What are the two components that make up ceramide?
sphingosine and fatty acid
What fatty acid is found in gray matter sphingomyelin?
stearic acid
What is a sign of lipid malabsorption?
steatorrhea (fatty stools)
What does sn stand for?
stereospecific numbering
What are the omega-3 fatty acid, eicosapentanoic acid's (EPA), functions?
thins blood and is an anti-inflammatory
What is another term for triglycerides (TGs)?
triacylglycerols (TAGs)
What are 95% of the lipids we consume and store?
triglycerides
What are the main lipids in our diet, and what percentage of total lipids are they?
triglycerides and ~95%
What does a TG structure resemble?
tuning fork
What lipoprotein is exogenous and indogenous?
very low density lipoprotein (VLDL)
What are the 5 water-soluble H donors?
vitamin C, glutathione, polyphenols, and BHA & BHT (synthetic)
How many double bonds do saturated fatty acids (SFA) have?
0
How many double bonds do monounsaturated fatty acids (MUFA) have?
1
What is the numbering of lauric acid?
12:0
How long are long chain fatty acids?
14-24 C
What is the numbering of myristic acid?
14:0
What is the numbering of palmitic acid?
16:0
What is the omega numbering for arachidonic acid (ARA)?
20:4ω6
What is the delta numbering for arachidonic acid (ARA)?
20:4∆5,8,11,14
What is the omega numbering of eicosapentaenoic acid (EPA)?
20:5ω3
What is the delta numbering of eicosapentaenoic acid (EPA)?
20:5∆5,8,11,14,17
What is the omega numbering of docosahexaeonic acid (DHA)?
22:6ω3
What is the delta numbering of docosahexaenoic acid (DHA)?
22:6∆4,7,10,13,16,19
How many kcal does 1 lb of fat contain?
3,500 kcal
How long are short chain fatty acids?
4-6 C
How much of a kcal deficit must a patient average (through diet & exercise) in order to lose 1 lb/week?
500 kcal deficit
How much of a kcal surplus must a patient average (through diet) in order to gain 1 lb/week?
500 kcal surplus
How long are medium chain fatty acids?
8-12 C
How many kcal/g do lipids provide?
9
What type of lipid is the "good cholesterol" containing mostly protein and removes cholesterol from cells?
HDL
What type of lipid is the "bad cholesterol" containing mostly cholesterol?
LDL
What is MUFA's impact on LDL, HDL, and heart disease risk?
LDL decreases, HDL decreases, and heart disease risk decreases
What is a PUFA's impact on LDL, HDL, and heart disease risk?
LDL decreases, HDL decreases, and heart disease risk decreases
What is trans fat's impact on LDL, HDL, and heart disease risk?
LDL increases, HDL decreases, and heart disease risk increases
What is SFA's impact on LDL, HDL, and heart disease risk?
LDL increases, HDL has no impact, and heart disease risk increases
Which of the following is an omega-3 fatty acid? a. 20:5 (Δ5,8,11,14,17) b. 20:4 (Δ5,8,11,14) c. 18:2 (Δ9,12) d. 22:4 (Δ7,10,13,16)
a. 20:5 (Δ5,8,11,14,17)
Food containing more SFA than UFA is most likely a ______? a. fat b. oil
a. fat
How far apart are double bonds on fatty acids?
always 3 C apart
What is the common name for the fatty acid with the delta numbering 20:4∆5,8,11,14?
arachidonic acid (ARA)
What is the common name for the fatty acid with the omega numbering 20:4ω6?
arachidonic acid (ARA)
How are fatty acids classified?
by the number of carbons (chain length) and the number of double bonds (saturation)
Long chain FA contain how many carbons? a. 4-6 b. 8-12 c. 14-24 d. 26-30
c. 14-24
What is the omega numbering of 20:4∆5,8,11,14? a. 20:4n-3 b. 20:4n-5 c. 20:4n-6 d. 20:4n-9
c. 20:4n-6
Which is the best source of oleic acid? a. corn oil b. butter c. olive oil d. soybean oil
c. olive oil
What does cis packing allow for a lipid?
can still rotate and acts like an oil, more fluff
Which end of the FA does ∆ start from?
carboxylic acid
What type of geometric isomer can still rotate?
cis
What is the delta numbering of 20:3n-6? a.20:3Δ14,17,20 b. 20:3Δ14,15,16 c. 20:3Δ12,13,14 d. 20:3Δ8,11,14
d. 20:3Δ8,11,14
Which of the following unsaturated fatty acids is one that can be made by the liver? a. linoleic acid b. lauric acid c. palmitic acid d. oleic acid
d. oleic acid
Partial hydrogenation of polyunsaturated fatty acids produces which of the following products that may increase your risk of heart disease? a. cis fatty acids b. alpha-linolenic acids c. gamma-linolenic acids d. trans fatty acids
d. trans fatty acids
What enzyme that adds double bonds does our body lack?
desaturases
What is the common name for the fatty acid with the delta numbering 22:6ω3?
docosahexaenoic acid (DHA)
What is the common name for the fatty acid with the delta numbering 22:6∆4,7,10,13,16,19?
docosahexaenoic acid (DHA)
What is the common name for the fatty acid with the delta numbering 20:5∆5,8,11,14,17?
eicosapentaenoic acid (EPA)
What is the common name for the fatty acid with the omega numbering 20:5ω3?
eicosapentaenoic acid (EPA)
What are the 5 roles of lipids in the body?
energy (during rest of long-term, low-intensity exercise), insulation and protection (surrounds organs), cell membrane integrity (phospholipids and cholesterol in plasma membrane), steroid hormones & hormone-like compounds (sex hormones, glucocorticoids & mineralocorticoids), and fat-soluble vitamin absorption (required for gallbladder contraction)
What do lipids contain a lot of in their reduced form?
hydrogen
What are the benefits from hydrogenating lipids?
improves shelf-life and converts softer fats to firmer fats
What are the risks from hydrogenating lipids?
increase risk of heart disease, type 2 diabetes, alzheimer's, colorectal cancer, breast cancer, prostate cancer, and barrett's esophagus
What is the common name for the fatty acid with the numbering 12:0?
lauric acid
What is the common name for the fatty acid with the omega numbering 18:2ω6?
linoleic acid
What are triglycerides, cholesterol esters, and phospholipids transported in?
lipoproteins
What type of lipid is stearic acid?
long chain saturated fatty acid
What type of lipid is lauric acid?
medium chain saturated fatty acid
What is the term which describes how PUFAs have a methyl group in between double bonds?
methylene interrupted
What type of fatty acid has 1 double bond and is generally oil at room temperature?
monounsaturated fatty acid (MUFA)
How many double bonds do polyunsaturated fatty acids (PUFA) have?
more than 1
What is the common name for the fatty acid with the numbering 14:0?
myristic acid
Is n-9 an essential FA?
no
Is there any trans double bonding in fully hydrogenated lipids?
no, it is a saturated fat
What type of lipids are liquid at room temperature?
oils
What is the common name for the fatty acid with the delta numbering 18:1∆9?
oleic acid
What is the common name for the fatty acid with the omega numbering 18:1ω9?
oleic acid
What type of fatty acid has no double bonds and is a fat at room temperature?
saturated fatty acids (SFA)
What are the classes of lipids?
simple lipids: free fatty acids (FFA), triglycerides (TGs), sterols and steroid; and complex lipids (something else attached to the lipid): phospholipids (phosphate) and glycolipids (carbs)
What is the common name for the fatty acid with the numbering 18:0?
stearic acid
What type of geometric isomer is stuck in linear position?
trans
What are most fatty acids found as?
triglycerides, cholesterol esters, and phospholipids
What type of lipid is arachidonic acid (ARA)?
unsaturated fatty acid
What type of lipid is docosahexaenoic acid (DHA)?
unsaturated fatty acid
What type of lipid is eicosapentaenoic acid (EPA)?
unsaturated fatty acid
What type of lipid is linoleic acid?
unsaturated fatty acid
What type of lipid is oleic acid?
unsaturated fatty acid
What type of lipid is α-linolenic acid (ALA)?
unsaturated fatty acid
Is n-6 an essential FA?
yes
Is there any trans double bonding in partially hydrogenated lipids?
yes
What is the common name for fatty acid with the delta numbering 18:3∆9,12,15?
α-linolenic acid (ALA)
What is the common name for the fatty acid with the omega numbering 18:3ω3?
α-linolenic acid (ALA)
