Brainscape's Knowledge GenomeTM

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


See full index

Biological Molecules > Lipids > Flashcards

Lipids Flashcards

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

Describe the structure of a triglyceride.

A

1 molecule of glycerol and 3 fatty acids.

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

What bond exists between a glycerol and fatty acid?

A

Ester bond.

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

Are triglycerides polar or non polar

A

Non polar.

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

Are triglycerides hydrophilic or hydrophobic?

A

Hydrophobic.

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

What functional group does glycerol have?

A

Hydroxyl

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

What functional group do fatty acid tails have?

A

Carboxylic acid.

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

How many carbon atoms could be found in a fatty acid group?

A

4-24

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

Describe how an ester bond is created when forming triglycerides.

A

The methyl group of the fatty acid undergoes a condensation reaction with the hydroxyl group of the glycerol, eliminating a water molecule, forming an ester functional group.

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

How are triglycerides able to store lots of energy?
How does this compare to carbohydrates?

A

High ratio of C-H bonds to C atoms in the hydrocarbon tail.
This means they can release more energy than the same mass of carbohydrates.

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

Why do triglycerides have no effect on the water potential of cells?

A

Triglycerides are insoluble in water so there is no effect on water potential.

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

How do triglycerides behave in water?

A

They clump together to form droplets.

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

What is a saturated fatty acid?

A

A fatty acid with a hydrocarbon chain containing single C-C bonds only.

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

What is an unsaturated fatty acid?

A

A fatty acid with a hydrocarbon chain consisting of C=C bonds as well as C-C bods

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

Where do saturated fats come from?

A

Animal sources.

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

Where do unsaturated fats come from?

A

Plant sources.

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

Describe the breakdown of triglycerides.

A

The triglyceride will undergo 3 hydrolysis reactions for each ester bond. This means 3 water molecules are required.

17
Q

Why are trans fatty acids more unhealthy than cis fatty acids?

A

Trans fatty acids can’t be metabolised by enzymes as the functional groups lie on opposite sides of the C=C bond. This means they can’t be broken down by the body, leading to coronary heart disease.

18
Q

Give 4 roles of fats.

A

Insulation
Organ protection
Energy source
Waterproofing

19
Q

Why are saturated fats bad for you?
What state are they at room temperature?
How do they affect cholesterols?

A

The straight hydrocarbon chain means fats can easily stack on top of each other.
They are solid at room temperature.
They cause LDL cholesterols to raise.

20
Q

Why are unsaturated fats more healthier than saturated fats?
What state are they at room temperature?
How do they affect cholesterols?

A

Unsaturated fats have a bent hydrocarbon chain. This means molecules cannot pack as tightly together.
This means they are liquid at room temperature.
They cause LDL cholesterols to lower and raise HDL cholesterols.

21
Q

Describe the structure of phospholipids.

A

1 glycerol molecule bonded to 2 fatty acids and 1 phosphate head.

22
Q

Why are phospholipids polar?

A

A dipole is present in the phosphate group, leading the phosphate head to be negatively charged, while the rest of the molecule is more positively charged.

23
Q

Why phospholipids hydrophillic or hydrophobic?
Why?

A

They are both.
This is because the phosphate head is polar, and therefore hydrophilic. The fatty acid tails are non polar and therefore are hydrophobic.

24
Q

Why do phospholipids form a bilayer?

A

The hydrophilic heads face outwards as they are attracted to water.
The hydrophobic tails point inwards towards each other so they can avoid water.

25
Q

Phospholipid bilayers allow for the diffusion of which type of molecules?

A

Small molecules such as water, and non polar molecules.

26
Q

Fatty acid tails repel which types of molecules?

A

Polar and charged molecules

27
Q

Describe the emulsion test for lipids.

A
  1. Mix the sample with ethanol in a clean test tube and shake.
  2. Add distilled water
  3. Shake the sample again
  4. If lipids are present, a cloudy white emulsion appears

Biological Molecules (9 decks)

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