Fats Flashcards

1
Q

How are lipids extracted/ separated

A

Dissolved in non-polar organic solvents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What chemical class do lipids belong to

A

Esters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does ‘lipids’ include

A

Fats, oils and steroid hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the difference between fats and oils

A

Fats are solid and oils are liquid at room temp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the similarity of fats and oils

A

Chemically the same

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are lipids used for

A

Concentrated energy source, provide thermal insulation, compartmentalise cells and organelles, act as chemical messengers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are lipids

A

Organic compounds containing carbon, hydrogen and oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What 4 groups can lipids be classified into

A

Fatty acids, FA derivatives, cholesterol and its derivative and lipoproteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the gender structure of a fatty acid

A

Methyl group, hydrocarbon chain and carboxylic acid group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which component of the fatty acid is hydrophobic

A

The methyl group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which component of the fatty acid is hydrophilic

A

The carboxylic acid group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the function of the hydroxyl in the carboxylic acid group on a FA

A

enables the FA acid to form ester bonds with other compounds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the range of carbon atoms in the hydrocarbon chain

A

Anything between 2 and 24 carbon atoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How many carbon carbon double bonds are in saturated fatty acids

A

None

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How many carbon carbon double bonds are in monounsaturated fatty acids hydrocarbon chain

A

One

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How many carbon carbon double bonds are in polyunsaturated fatty acids hydrocarbon chain

A

2-5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How are fatty acids sub classified

A

Short, medium and long chain FA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which FA type occur free

A

Short chain only

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How can the degree of unsaturation be measured in fatty acids

A

The iodine value is used as iodine reacts with the double bond so the degree of unsaturation is calculated from iodine absorbed

20
Q

What 2 forms can unsaturated fatty acids occur in

A

Cis- and trans-

21
Q

What is whether an unsaturated FA being cis or trans dependent on

A

The position of the carbon carbon double bonds

22
Q

What is the difference between cis and trans fatty acids

A

In cis the hydrogen atoms associated with the carbon carbon double bond are on the same side of the fatty acid so the molecule occupies more space and is more fluid due to angle produced (natural) while in trans the hydrogen atoms associated with the carbon carbon double bond are on the opposite sides so the molecule is more rigid and linear (processed)

23
Q

What are th two essential fatty acids

A

Linoleic acid (n-6) and alpha-linolenic acids (n-3)

24
Q

How many carbon atoms and soluble carbon carbon bonds does fatty acid C18:2 have

A

18 carbons, 2 dd carbon bonds

25
Q

How is the position of the double double carbon bonds indicated from the carboxylic acid end

A

Delta and the number of the carbon atoms where there is double bonds

26
Q

How is the position of the double double carbon bonds indicated from the methyl end

A

n-the number of the carbon atom where the double bond is

27
Q

Why are linoleic and alpha linolenic acids important in the body

A

Precursors for synthesis of eicosanoids which are associated with many bodily functions

28
Q

How many fatty acids can attach to a glycerol backbone in lipids

A

1-3

29
Q

What are phospholipids

A

Glycerol molecules associated with a phosphate group and two fatty acids

30
Q

What does Amphiphilic mean

A

Both hydrophilic and hydrophobic components

31
Q

What is the import of the phosphate group in phospholipids

A

Can associate with other functional groups

32
Q

Which component of cholesterol is hydrophilic and where does it align in cell membranes

A

Hydroxyl group, aligns with phospholipid head

33
Q

Which component of cholesterol is hydrophobic and where do they align in membranes

A

Rings with many methyl group, aligns with fatty acid tails

34
Q

Do we need cholesterol is our diet

A

No as it is synthesised in the liver as long as we have efficient endogenous synthesis

35
Q

How does cholesterol form esters

A

Hydroxyl group reacts with a fatty acid

36
Q

What is the role of cholesterol in cell membranes

A

Reduces fluidity

37
Q

What are the roles of cholesterol in the body

A

Precursor for biosynthesis of steroid hormones, biles salts and involved in cell signaling and transport of fatty acids and formation of mylein sheath neurones

38
Q

How are lipids digested

A

Emulsified by bile salts, hydrolysis by lipases into monoglycerides and fatty acids, combined with bile salts to form micelles and transported to epithelial cell of intestine

39
Q

How are lipids absorbed

A

Resynthesised into triglycerides and packaged into chylomicrons with cholesterol, phospholipids and free fatty acids for exocytosis to lymphatic system

40
Q

What is the role of lipoprotein lipase in lipid transport and uptake

A

Facilitates hydrolysis of triglycerides in the chylomicron so they can be taken up by muscle cells or stored as TAG in adipose tissue

41
Q

What happens to the depleted chylomicron remnant after the triglycerides have been hydrolysed and taken up

A

Returned to the liver

42
Q

What is a VLDL

A

Very low density lipoprotein, similar in structure to chylomicrons used to facilitate uptake of triglycerides by muscle and adipose tissue

43
Q

How many kJ of energy in one gram of fat

A

37kJ

44
Q

What is recommended % of total energy from fat

A

<35%

45
Q

What process is used to produce trans fats

A

Hydrogenation