Chapter 10 Lipids

Question 1

What are lipids soluble in and NOT soluble in?

Answer 1

Soluble: in non polar solvents

NON soluble: H2O bc its amphipathic

Question 2

What are some examples of lipids?

Answer 2

fats, oils, waxes, most non protein components of the membranes

Question 3

What are 3 functions of lipids?

Answer 3

1) Major form of stored energy in biological systems
2) Major components of biological membranes
3) Hormones

Question 4

Lipids are highly ______

Answer 4

saturated, because of the more protons the more energy can be derived rather than carbohydrates

Question 5

______ can retain more water, so it has more storage capabilities than lipids

Answer 5

Glycogen

Question 6

What are the 5 different types of lipids?

Answer 6

1) Fatty Acids: a common fuel
2) Triacylglycerols: storage form of fatty acids
3) Phospholipids: membrane lipids
4) Glycolipids: membrane lipids composed of carbohydrates attached to it
5) Steroids: polycyclic hydrocarbons with a variety of functions

Question 7

What are the characteristics of fatty acids?

Answer 7

Long, unbranched, saturated (more hydrogens) chain carboxylic acid (AKA the head group)

Question 8

What are fatty acids derived from?

Answer 8

From the hydrolysis of fats, vegetable oils or phosphodiacylglycerols of biological membranes.

Question 9

Saturated fatty acid means?

Answer 9

No double bonds present

Question 10

Unsaturated fatty acid means?

Answer 10

Double bonds are present

Question 11

How do you number fatty acids?

Answer 11

The first carbon begins at the carboxylic acid end

Question 12

Systemic naming of fatty acids

Octadecanoate

Answer 12

Means there are 18 C’s present with no double bonds (saturated) and -ate is the acidic part

Question 13

Systemic naming of fatty acids

Octadecenoate

Answer 13

Means there are 18 C’s presents, with double bonds (Unsaturated) and -ate is the acidic part

Question 14

Laurate—Saturated or unsaturated? # of C’s?

Answer 14

12 saturated

Question 15

Myristate—Saturated or unsaturated? # of C’s?

Answer 15

14 saturated

Question 16

Palmitate—Saturated or unsaturated? # of C’s?

Answer 16

16 saturated

Question 17

Stearate—Saturated or unsaturated? # of C’s?

Answer 17

18 saturated

Question 18

Arachidate—Saturated or unsaturated? # of C’s?

Answer 18

20 saturated

Question 19

Arachidonate—Saturated or unsaturated? # of C’s?

Answer 19

20 UNsaturated

Question 20

What is the effect of chain length on melting temperature?

Answer 20

Smaller/less compact/less C’s chain length, lower melting temp
Longer/more compact/ more C’s chain length, higher melting temp

Question 21

What is the effect of unsaturation on melting temperature?

Answer 21

double bonds prevent tight packing, so LOWER temp

Question 22

What are good fats?

Answer 22

high in cis polyunsaturated fats.

ex: vegetable oils, like olive, canola, sunflower

Question 23

What are bad fats?

Answer 23

high in saturated fats.

ex: stearic (beef); palm & coconut oils (found in candy)

Question 24

What are really bad fats?

Answer 24

trans fatty acids, result from partial hydrogenation of vegetable oils. Margarine has trans fatty acids.

This is because it is difficult to metabolism; lead to increased cholesterol
levels in the blood stream

Question 25

What do omega 3's do?

Answer 25

They help reduce the physical harm caused by smoking, reduce the risk of advanced prostate cancer, and helps your heart

Question 26

How do you know if you have an omega 3 or omega 6?

Answer 26

Start counting from opposite side of the carboxylic acid and if the double bond starts on the 3 C from the end then it would be omega 3

Question 27

What is a triacylglycerol?

Answer 27

It is a stored form of fatty acids and it contains 3 fatty acids + glycerol

Question 28

Where are triacylglycerol's located?

Answer 28

Located in adipocytes in adipose tissue

Question 29

What are triacylglycerol's function?

Answer 29

Store energy for a later use

Question 30

Esterfication while making triacylglycerols

Answer 30

COOH reacts with the OH group

Question 31

Saponification of triacylglycerols

Answer 31

reactions of glyceryl ester with sodium or potassium hydroxide to produce a soap, which is the corresponding salt of the long-chain fatty acid.

Question 32

What can the backbone of phospholipids be?

Answer 32

Glycerol =glycerophospholipids or phosphoglycerides | Sphingosine= Sphingolipids

Question 33

What are the four components of phospholipids?

Answer 33

2 fatty acids, glycerol or sphingosine (platform), phosphate group, and an OH group

Question 34

Phospholipids with a glycerol platform are called _______?

Answer 34

phosphoglycerides or phosphoglycerols.

Question 35

The major phospholipids are derived from ______?

Answer 35

phosphatidate

Question 36

What is the most abundant group of lipids?

Answer 36

Phosphoglycerides which are derived from phosphatidic acid- palmitic, stearic and oleic acid

Question 37

Phospholipids built on a sphingosine platform are called _________?

Answer 37

sphingolipids

Question 38

Sphingomylein is a common membrane sphingolipid and is especially common in the ______?

Answer 38

myelin sheath of nerve cells

Question 39

What are the four components of a sphingolipid?

Answer 39

Sphingosine, 1 fatty acid (attached by an amide bond), PO4, and choline

Question 40

What are glycolipids?

Answer 40

They have a carbohydrate attached to lipids, which are embedded in membrane(lipid) and the carbohydrate is on surface of membrane. They also have a sphingosine backbone and is important with communication

Question 41

What are glycolipids composed of?

Answer 41

Sphingosine backbone with fatty acid and sugar unit (carbohydrate)

Question 42

What are steroids?

Answer 42

Hormones, Precursors of cholesterol, and are apart of membrane components

Question 43

What is cholesterol and its function?

Answer 43

``` membrane component Precursor of bile Precursor of hormones (in charge of making hormones) Absent in prokaryotes Maintains membrane fluidity AMPHIPATHIC ```

Question 44

What is so special about the membrane lipid from the archaeon?

Answer 44

archaeon can live in harsh conditions bc the arrangement of fatty acids are used for insulation. You have and ether as well as branched molecules of methyl groups which allow to live under extreme pH high temperatures. It is also able to avoid hydrolysis and oxidation of membranes