Module 3 Lipids (Part 3)

Fats

Have higher melting points; they are solids at room temperature. Derived from fatty acids with few double bonds.

Oils

Have lower melting points; they are liquids at room temperature. Derived from fatty acids having a larger number of double bonds.

Fats

Are used to build cell membranes, insulate the body, and store energy for later use.

20-35%

It is recommended that no more than _________ of a person’s caloric intake should come from lipids.

Cholesterol Synthesis

Saturated fats stimulate ______________, which can lead to cholesterol plaques building up inside arteries.

High blood pressure, Heart attack and Stroke

Cholesterol plaques building up inside arteries results to _________________.

Unsaturated Triacylglycerols

______________ lower the risk of heart disease by decreasing the level of cholesterol in the blood.

Omega-3 Fatty acids

Triglycerols formed from _____________ are very helpful in lowering the risk of heart attack.

Trans

If the double bond of the unsaturated triacylglycerol is ____________, the beneficial effect is lost.

Trans fats

____________, which are primarily synthesized instead of naturally occuring, act like saturated fats and increase the cholesterol levels in the blood.

Hydrolyzed

Triacylglycerols are ____________ with water in the presence of acid, base, or enzymes (In the body)

Adipose Cells

Humans store energy as Triacylglycerols in the _____________ below the surface of the skin, breast area, and surrounding internal organs.

Constant

The number of Adipose cells is ___________

Swell or Shrink

Weight gained or lost causes Adipose cells to ____________, but not decrease or increase in number.

Lipases

To metabolize Triacylglycerols for energy, the esters are hydrolyzed by enzymes called __________.

CO2, H2O, and Great deal of energy

Complete Metabolism of a Triacylglycerol yields ________________

Basic Hydrolysis

Soaps are metal salts of fatty acids prepared by _____________ (Saponification) of a triacylglycerol.

Sodium Stearate

Is the salt of stearic acid and the most common soap.

Polar head

Ionic end

Nonpolar Tail

Nonpolar end

Non polar tails

The ____________ dissolve grease and oil and the Polar head makes it soluble in water.

Polar head

The Nonpolar tails dissolve grease and oil and the ______________ makes it soluble in water.

Lard, Tallow, Coconut oil or Palm oil

Soaps are made from _________________

Lard

From hogs or pigs

Tallow

From cows or sheep

Lipid source, Length of C chain, and Degree of unsaturation

All soaps work in the same way, but have different properties depending on the __________________

Phospholipids

Are lipids that contain a P atom

Phosphoacylglycerols and Sphingomyelins

Two common types of Phospholipids are __________________

Phosphoacylglycerols

_______________ are the main component

Phosphodiester bonded to an alcohol

Structurally, they resemble a Triacylglycerol except the third fatty acid has been replaced with ______________

Cephalin

One of the main types of Phosphoacylglycerol is ___________

Phosphatidylethanolamine

Cephalin

Lecithin

The second of the main types of Phosphoacylglycerols is __________

Phosphatidylcholine

Lecithin

Two Nonpolar “tails”

The two fatty acid side chains form _____________ that lie parallel to each other.

Polar “Head”

The phosphodiester end of the molecule is a charged or _____________

Sphingomyelins

___________ do not contain a glycerol backbone, they have a sphingosine backbone instead.

Amide bond

Sphingomyelins do not contain an ester, their single fatty acid is bonded to the backbone by an ____________.

Myelin sheath

The coating that surrounds nerve cells that is rich in sphingomyelins.

Cell

The basic unit of living organisms is the _________.

Cell Membrane

The ___________ surrounds the cytoplasm, the aqueous medium inside the cell.

Barrier

The Cell membrane acts as a __________ to stop the passage of ions and molecules into or out of the cell. The other job of the membrane is to allow nutrients in and waste out.

Selectively Permeable

A Cell membrane is _____________.

Phospholipids

____________ the major component of cell membranes, contain a hydrophilic polar head and two hydrophobic nonpolar tails.

Lipid bilayer

When Phospholipids are mixed with water, they assemble in a _____________

Proteins and Cholesterol

______________ are embedded in the lipid bilayer membrane.

Peripheral Proteins

____________ are embedded within the membrane and extend outward on one side only.

Integral Proteins

_________ extend through the entire bilayer

Glycolipids and Glycoproteins

Sometimes Carbohydrates are attached to the exterior of the cell forming ___________

O2 and CO2

Small molecules like __________ can diffuse through the cell membrane, traveling from higher to lower concentration.

Facilitated transport

Larger polar molecules need ____________ to cross efficiently.