Lipids Flashcards
1
Q
phospholipids
A
- phosphate and alcohol that comprise polar head
- phosphodiester linkage joins this head to the FA hydrophobic tail
2
Q
glycerol forms the backbones of…
A
- phosphoglycerides
3
Q
true or false: sphingolipods are phospholipids
A
false; some are some aren’t
4
Q
fully saturated fatty acids
A
- only have single bonds
- carbon saturated w no pi bonds
- solid at room temp
- greater van der Waals forces, more stable overall structure
5
Q
unsat FA
A
- double bonds
- kinks
- fluidity
- liquid at room temp
6
Q
glycerophospholipids
A
- glycerol backbone bonded by ester linkages to 2 FA and by a phosphodiester linkage to a highly polar head group
- head group can be neutral or have a charge
- important for cell signaling, recognition, and binding
7
Q
phosphatidylcholine
A
- glycerophospholipid
- choline head group
8
Q
phosphatidylethanolamine
A
- glycerophosholipid with ethanol-amine head group
9
Q
sphingolipids
A
- example is the cell-surface antigens on RBCs vital to ABO blood typing
- sphingoid backbone OR sphingosine
- long-chain nonpolar FA tails and polar head groups
- many are also phospholipids because of phosphodiester linkage
- others contain glycosidic linkages to sugars; glycolipid
10
Q
4 types of sphingolipids
A
1) ceramides
2) sphingomyelins
3) glycosphingolipids
4) gangliosides
11
Q
ceramides
A
- sphingolipids
- has a single H atom as it’s head group
12
Q
sphingomyelins
A
- sphingolipid
- phospholipid
- either have phosphocholine or phosphoethanolamine group, meaning there is a phosphodiester bond somewhere
- head groups have no net charge
- major components in the plasma membranes of cells producing myelin (oligoden. & Schwann)
13
Q
glycosphingolipids
A
- sphingolipid
- not phospholipids
- contain no phosphodiester linkage
- found outside of plasma membrane
- can be split into cerebroside or globoside
- neutral, no net charge in physiological pH
cerebroside: singular sugar
globoside: have two or more sugars
14
Q
gangliosides
A
- sphingolipid
- polar head groups and composed of oligosaccharides with one or more N-acetylneuraminic acid (NANA) molecules at the terminus and a negative charge
- glycolipids, glycosidic linkage and no phosphate group
- major role in cell interaction, recognition, and signal transduction
15
Q
waxes
A
- esters of long FA chains w long-chain alcohols
- pliable solids at room temp
- keep water in and from getting in and pests out
16
Q
terpenes
A
- odiferous
- metabolic precursors to steroids and other lipid signaling molecules
- varied independent functions
- built from isoprene (C5H8)
- steroid synthesis
17
Q
monoterpenes
A
- terpene
- (C10H16)
- 2 isoprene units
- essential oils and
18
Q
sesquiterpenes
A
- terpene
- 3 isoprene units
19
Q
diterprene
A
- terpene
- 4 isoprene units
20
Q
triterpene
A
- terpene
- 6 isoprene units
- converted to cholesterol and various steroids
21
Q
carotenoids
A
- terpene
- tetraterpenes w 8 isoprene units
22
Q
terpenoids
A
- isoprenoids
- derivatives of terpenes that have undergone oxygenation and rearrangement of the carbon skeleton
- adding a variety of functional groups to modify
- similar functions as terpenes
- similar naming conventions (diterpenoids meaning 4 isoprene units)
- important in steroid formation
23
Q
steroids
A
- derivatives of terpenes
- 4 cycloalkane rings fused together: 3 cyclohexane, 1 cyclopentane
- functionality determined by oxidation status of rings, as well as functional groups they carry
- nonpolar
24
Q
steroid hormones
A
- travel on protein carriers
- bind to specific high-affinity receptors and alter gene expression levels
25
Q
cholesterol
A
- major component in phospholipid bilayer and is responsible for mediating membrane fluidity
- amphipathic
- hydrophilic heads and hydrophobic tails
- keeps cell membrane from solidifying or becoming too permeable
- precursor to steroid hormones, bile acids, and vitamin D
26
Q
prostaglandins
A
- unsat CA derived from arachidonic acid
- contain 1 five-C ring
- paracrine or autocrine signaling
- regulate cAMP synthesis
- intracellular messenger, mediating the actions of many other hormones
- NSAIDs aid in inhibiting COX, which aids in prostaglandin production
27
Q
vitamin A
A
- carotene
- unsat hydrocarbon important in growth and development, vision, and immune function
- most significant metabolite of it is the aldehyde form, retinal important in light-sensing in eye
- retinol is the storage form, oxidized to retinoic acid which is a hormone that regulates gene expression during epithelial development
28
Q
vitamin D
A
- cholecalciferol
- UV light-driven skin rxn
- converted to calcitriol in the liver and kidneys
- inc Ca and phosphate uptake in the intestines
- promotes bone production
- lack causes rickets
29
Q
vitamin E
A
- tocopherols (biological antioxidants) and tocotrienols
- substituted aromatic ring with a long isoprenoid side chain
- hydrophobic
- aromatic ring reacts with free radicals destroying them
- prevents oxidative damage (this damage contributed to cancer and aging)
30
Q
vitamin K
A
- group of compounds (phylloquinone and menaquinone)
- vital to postransaltional modifications required to form prothrombin (aromatic ring undergoes redox to form this)
- important for calcium binding
31
Q
triacylglycerols
A
- more reduced, oxidation yields double the energy as carbs
- hydrophobic
- energy storage and insulation
- 3 FA bonded by ester linkages
- oily droplets in cytosol
- metabolic fuel
- adipocytes
- travel bidirectionally between liver an adipose tissue
32
Q
free FA
A
- unesterified FA
- free carboxylate group
- circulate in blood bonded noncovalently to serum albumin
- make up soap via saponification
33
Q
saponification
A
- ester hydrolysis of triacylglycerols using a strong base
- base usually used as lye (sodium or potassium hydroxide)
- result in basic cleave of a FA leaving the sodium salt of the FA and glycerol
34
Q
surfactant
A
- lowers surface tension at the surface of a liquid, serving as a detergent or emulsifier
- micelles
35
Q
micelles
A
- important in absorption of fat soluble vitamins and complicated lipids
