Lipid Structure 5. BioChem

Question 1

Lipids

Answer 1

1. Identity:
   I. Nonpolar, insoluble substances unless in
   nonpolar organic solvents
2. Functions:
   I. Structural building blocks
   A. Phospholipids & sterols give rise to vesicles,
   liposomes & membranes
   II. Signaling
   A. Intracellular messengers
   B. Hormones
   III. Energy Storage reservoirs

Question 2

Structural Lipids

Answer 2

1. Phospholipids
2. Glycerophospholipids
3. Sphingolipids
4. Waxes

Question 3

Structures Formed Upon Interaction of Amphipathic, Structural Lipids

Answer 3

1. Micelles
2. Liposomes
3. Phospholipid Bilayer

Question 4

Phospholipids

Answer 4

Structure:
I. Amphipathic structural lipid with a polar head
[composed of alcohol and phosphate] bonded to a
nonpolar tail [composed of fatty acids] with a
phosphodiester bond

Categorized based on:
I. Backbone Type—-ex. Glycerophospholipids &
Sphingophospholipids
II. Polar-Head Type
III. Fatty-Acid Type & Length

Question 5

Fatty Acids

Answer 5

Identity:
I. Nonpolar tail components of amphipathic lipids
Types:
I. Saturated
D: single bonded hydrocarbons that give lipids a
solid nature
II. Unsaturated
D: Hydrocarbons w/ 1+ double bonds & w/ kinks
that prevent them from stacking in solid forms;
giving them a liquid nature

Question 6

Glycerophospholipids

Answer 6

-AKA: Phosphoglyceride:

1. Identity
   - A subcategory of phospholipids with a glycerol backbone that is bound to 2 fatty acids [of various length and saturation] with ester bonds and to a highly polar head group [of distinct nature] with a phosphodiester bond
2. Functions
   I. Important in cell-signalling
   II. Cell Recognition
   III. Cell-binding

Ex.
Polar head-group———— Glycerophospholipid

1. Choline———Phosphatidylcholine
2. Ethanolamine——–Phosphatidylethanolamine

Question 7

Sphingolipids

Answer 7

I. Types:
1. Ceramide
A. Has a single H as its head group
2. Sphingomyelins/Sphingophospholipids
A. Head groups:
1. Choline or Ethanolamine
B. Bond Type:
1. Phosphodiester
C. Head Charge:
1. Neutral
D. Function:
1. Plasma membrane component of myelin
producing cells such as oligodendrocytes
& Schwann cells
**Type: phospholipid
3. Glycosphingolipids
A. Head groups:
1. Sugar molecules
AA. Categories:
1. Cerebroside—1 sugar head
2. Globoside—–2+ sugar heads
B. Bond Type:
1. Glycosidic bonds
C. Head Charge:
1. Neutral
D. Function
1. Contribute to cell recognition due to their
presence on cell surface
***Type: Glycolipid
4. Gangliosides
A. Head Type:
1. Oligosaccharides with 1+ NANA/Sialic acid
molecule
B. Bond Type:
1. Glycosidic bonds
C. Head Charge:
1. Negative
D. Function:
1. Cell Recognition
2. Cell Interaction
3. Signal Transduction
**Type: Glycolipid

Question 8

Waxes

Answer 8

Identity:
I. Structural lipid with long fatty-acid and alcohol
chains that form pliable solids at RT
Function:
I. Protect against excessive dehydration
2. Protect against parasites
3. Serve as a
A. Shelter
B. Lubricant
C. Water-repellent to keep skin dry