TR3.5

Structure of lipids, Fatty Acids, Glycerol

Houjun Liu 2021-09-27 Mon 12:00

1 Structure of Lipids

1.1 Fatty acids

Screen Shot 2020-09-09 at 2.58.49 PM.png

Figure 1: Screen Shot 2020-09-09 at 2.58.49 PM.png

A single penteine and embellishments. Single Fatty acids = Glycerol

1.2 Trygricerol

Fat! (a.k.a. adapose tissue) = Triglycerol: three fatty acids together.

Fat_triglyceride_shorthand_formula.png

Figure 2: Fattriglycerideshorthandformula.png

1.2.1 Saturated vs. Unsaturated fats

Saturate Fats No double bonds in the carbon chain — think! butter

Unsaturated Fats Double bonds in the carbon chain — think! olive oils

Saturated fats has a higher melting point then the unsaturated fats, but unsaturated fats have double bonds whereas saturated fats have single bonds only. Why?

  • Double bonds, due to their caused VESPR geometry (and hence the -1 hydrogen), are curved. This makes it harder to stack together, causing a lower melting point
  • Single bonds, due to their caused VESPR geometry, is flat. This makes them easier to stack together, causing a higher melting point.

1.3 Phosophilids

2 fatty acids (hydrophobic) + phosphate group (hydrophillic)

Screen Shot 2020-09-09 at 3.15.41 PM.png

Figure 3: Screen Shot 2020-09-09 at 3.15.41 PM.png

A combination of many of these will end up with membrane: Screen Shot 2020-09-09 at 3.08.10 PM.png

The hydrophobic tail stays inside, and the hydrophillic head pokes outside and attracts water.

1.4 Liposomes + micelles

Lots of phosophillids

Screen Shot 2020-09-09 at 3.11.54 PM.png

Figure 4: Screen Shot 2020-09-09 at 3.11.54 PM.png

A same idea as Phosophilids, but instead in a big wad of Phosolipids. this arrangement is also how basic cells form membranes. KBhBIO101CellMembraines

1.5 Steroids

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Figure 5: Screen Shot 2020-09-11 at 2.43.35 PM.png

Steroids typically are lipids that contain a ring structure, which usually contains 17 carbon lipids with rings formed by 5-6 carbons each