Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

bio > Lipids > Flashcards

Lipids Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

What elements make up lipids ?

A

C, H, O

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

Are lipids soluble in water and organic solvents ?

A

Insoluble in water
Soluble in organic solvent

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

Are lipids polar or non-polar ?

A

Non-polar and hydrophobic

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

What are the three groups of lipids ?

A

Simple lipids
Complex lipids
Steroids and sterols

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

How are simple lipids formed ?

A

By joining fatty acids to an alcohol by ester linkages

Eg. Triglyceride, waxes

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

What are complex lipids made up of ?

A

A lipid and a non-lipid component

Eg. Phospholipids, glycolipids

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

What are steroids and sterols characterised by ?

A

Carbon skeleton consisting of four fused rings (steroid nucleus)

Eg. Cholesterol

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

What is a glycerol ?

A

An alcohol with three -OH groups

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

Are glycerols soluble water ?

A

Yes - the OH groups can interact with water

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

What are fatty acids ?

A

Long chained carboxylic acids contain an even number of carbon atoms
- consist of a long hydrocarbon chain (fatty acid tail) and a carboxylic acid group

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

Which parts of te fatty acid are hydrophobic, which are hydrophilic ?

A

Long hydrocarbon chain is hydrophobic
Carboxylic acid is hydrophilic

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

What does the melting point of difference fatty acids depend on

A

The degree of saturation and the length of the hydrocarbon chain

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

What are saturated fatty acids ?

A

No C=C
Each carbon has maximum number of H atoms attached

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

What are unsaturated fatty acids ?

A

C=C present creating a ‘kink’ in hydrocarbon tail

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

As number of C=C increase, does MP increase or decrease ?

A

Decrease

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

Why does MP decrease as number of C=C increase ?

A

Greater number of C=C means greater number of kinks
There is thus weaker intermolecular interaction between fatty acid molecules, lesser energy is required to weaken the hydrophobic interactions

17
Q

As length of hydrocarbon tail increase, does MP increase or decrease ?

A

Increase

18
Q

Why does MP increase when length of hydrocarbon tail increase ?

A

The longer the tail, the larger the surface area available for hydrophobic interactions between the hydrocarbon chains thus larger amounts of energy needed to weaken the interactions

19
Q

What makes up a triglyceride ?

A

1 glycerol + 3 fatty acids

20
Q

What is the bond joining the fatty acids to the glycerol in triglyceride ?

A

Ester bond

21
Q

How is triglyceride formed ?

A

Condensation reaction where a molecule of water is removed to form -COO- (ester bond)

22
Q

What are the five functions of triglyceride ?

A
  1. Storage form of energy
  2. Source of metabolic water
  3. Good thermal insulator (blubber)
  4. Provides buoyancy to aquatic mammals
  5. Protective layer for delicate internal organs
23
Q

What properties of triglyceride allows it to be a good storage material ?

A

Large and uncharged hence insoluble in water
- can be stored in large amounts without affecting WP of cell and can be prevented from diffusing out of cells

24
Q

Why is triglyceride a good store of energy ?

A

For the same weight, triglycerides yields twice the quantity of energy compared to carbs
- lipids are more reduced than carbs, more oxidation steps are needed to fully oxidise lipids thus more ATP formed

25
Q

What is metabolic water ?

A

Water produced from oxidation of food, very important to desert animals

26
Q

Why are triglycerides a good source of metabolic water ?

A

Triglycerides yield 2x more H atoms than carbs thus better source of water
- H atoms give water upon oxidation

27
Q

Why is triglyceride a good thermal insulator ?

A

Prevents excessive heat loss, important in aquatic animals

28
Q

Why does triglyceride provide buoyancy to aquatic animals ?

A

It is less dense than water

29
Q

what are phospholipids made out of ?

A

1 glycerol + 2 fatty acids + a phosphate group (negatively charged)

30
Q

How is phospholipids formed ?

A

Through 2 condensation reactions
- one where fatty acid is joined to glycerol, forming ester bond and producing 1 mole of water
- one where phosphate group is joined to glycerol, forming phosphoester bond and producing water

31
Q

What is a phospholipid ?

A

A complex lipid
A major component of cell membrane

32
Q

Are phospholipids hydrophobic or hydrophilic ?

A

They are amphipathic (both hydrophobic and hydrophilic regions present)
- hydrocarbon tails are hydrophobic
- phosphate heads are hydrophilic

33
Q

What are the 4 functions of phospholipid ?

A

Form a bilayer due to their amphipathic nature

Allows for compartmentalisation (separation) of cell contents from aqueous external cell environment

Allows for formation of organelles within cell where specialised biochemical reactions occur

Variations of phospholipids affect fluidity and thus permeability of membrane

34
Q

What is the structure of the phospholipid bilayer ?

A

Polar, hydrophilic heads point outwards and make contact with water molecules
Non-polar, hydrophobic hydrocarbon tails point inwards, forming hydrophobic core

35
Q

How is a variety of phospholipids formed ?

A

Addition of small molecules to the phosphate group
Degree of saturation
Length of fatty acids

bio (23 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions