Lipid structure and function

Question 1

Structure and Function of Lipids

Answer 1

-Amphipathic: they have both hydrophobic tails and hydrophilic heads, allowing the formation of bilayers in aqueous solutions

Question 2

Fatty acid tails

Answer 2

structural role and make a bulk of the phospholipid bilayer

Question 3

polar head

Answer 3

determines functional differences between membrane lipids due to its constant exposure to exterior environment of the phospholipid bilayer

Question 4

Glycerophospholipids

Answer 4

Phospholipids with glycerol backbone

They have: a polar head, glycerol, and two fatty acid tails

Question 5

Sphingolipids

Answer 5

Contain a sphingosine or sphingoid

Not all phospholipids

Question 6

What is the difference between a sphingolipid that is also a phospholipid and one that is not?

Answer 6

• The difference is in the bond between sphingosine backbone and the head group.
• When its a phospholipid it is a phosphodiester bond
• When its a nonphospholipid sphingolipids including glucolipids, they contain a glycosidic linkage to sugar.

Question 7

What are the three main types of sphingolipids

Answer 7

types of sphingolipids: ceramides, phosphosphingolipids (sphingomyelins), and glycosphingolipids, which differ in the substituents on their head group.Nov 29, 2003

Question 8

Sphingomyelin

Answer 8

• Phospholipid
• Contains either a phosphatidylethanolamine or phosphatidylcholine
• Component of myelin sheath

Question 9

Glycosphingolipid

Answer 9

• Glycolipid
• Contains sugars
  -Cerebrosides- single sugars
  Globosides- two or more sugars
• outside of plasma membrane

Question 10

Ganglioside

Answer 10

• Glycolipid
• Contains oligosaccharides or N-acetylneuraminic acid (NANA)
• most complex
• cell interactions, recognition and single transduction

Question 11

Waxes

Answer 11

Esters of long-chain fatty acids with long -chain alcohols

- protection for plants and animals (prevent dehydration)

Question 12

Terpenes

Answer 12

Odiferous steroid precursors made from isoprene (C5H8)

Single terpene unit has 2 isoprene- monoterpene (C10H16)

Question 13

3 isoprene units

Answer 13

Sesquiterpenes

Question 14

4 isoprene units

Answer 14

Diterpenes

Question 15

6 isoprene units

Answer 15

Triterpenes

Question 16

8 isoprene units

Answer 16

Tetraterpenes

Question 17

What is the difference between steroid and steroid hormone?

Answer 17

Steroid (derivative of terpenes) defined by its structure: it includes three cyclohexane rings and a cyclopentane ring.

A steroid hormone is a molecule within this class that also functions as a hormone - it travels in the bloodstream, is active at low concentrations, has high-affinity receptors, and affects gene expression and metabolism.

Question 18

Prodtaglandins

Answer 18

Autocrine and paracrine signaling molecules that regulate cAMP levels which is regulated in many pathways, including those that drive pain and inflammation.

Question 19

What are the 4 fat soluble vitamins

Answer 19

K, E, A, D

Karen Eat Apples Daily

Question 20

Vitamin A

Answer 20

Carotene
Vision; metabolized to retinal (aldehyde form) for vision and retinoic acid for gene expression in epithelial development

Question 21

Vitamin D

Answer 21

Cholecalciferol

Calcium and phosphate regulation and needed for bone formation

Question 22

Vitamin E

Answer 22

Tocopherols
Biological antioxidants and their aromatic rings destroy free radicals, preventing oxidative damage
hydrophobic

Question 23

Vitamin K

Answer 23

Phylloquinone and Menaquinones

post-translation modification of prothrombin, addition of calcium -binding sites on many proteins

Question 24

How does the human body store energy? Why doesn’t it store most of it as sugar

Answer 24

Human body stores spare energy as glycagen and triacylglycerols. Triacylglycerols are preferred because their carbon are more reduced. resulting in a larger amount of energy yield per unit weight. In addition, due to their hydrophobic nature, triacylglycerols do not need to carry extra weight from hydration.

Question 25

What is the structure and function of triacylglycerols?

Answer 25

Also called triglycerols

- composed of glycerol backbone esterified to three fatty acids. They are used for energy storage

Question 26

Why does soap appear to dissolve in water?

Answer 26

Soap appears to dissolve in water because amphipathic fatty acid salts form micelles, with hydrophobic fatty acid tails toward the center and carboxylate groups facing outward toward the water. Fat soluble particles can then dissolve inside micelles in the soap water solution and wash away.

Question 27

Surfactant

Answer 27

lowers the surface tension at the surface of a liquid, serving as detergent or emulsifier.

Question 28

Sopanification

Answer 28

Ester hydrolysis of triacylglycerols using a strong base to form glycerol and fatty acid salts