Lipids

Question 1

What are the two main types of lipids?

Answer 1

Triglycerides and phospholipids

These are the primary classifications of lipids based on their structure and function.

Question 2

What is a triglyceride made up of?

Answer 2

One glycerol and three fatty acids

Triglycerides serve as energy-storage molecules.

Question 3

What is a phospholipid made up of?

Answer 3

One glycerol, two fatty acids, and one phosphate group

Phospholipids are essential for forming cell membranes.

Question 4

What holds triglycerides and phospholipids together?

Answer 4

Ester bonds

Ester bonds are a type of covalent bond that link glycerol and fatty acids.

Question 5

What distinguishes saturated fatty acids from unsaturated fatty acids?

Answer 5

Unsaturated fatty acids contain carbon-carbon double bonds

Saturated fatty acids have no double bonds between carbon atoms.

Question 6

Describe the solubility characteristics of triglycerides.

Answer 6

Insoluble in water but soluble in ethanol

This property helps maintain cell water potential.

Question 7

What is the hydrophilic part of a phospholipid?

Answer 7

The phosphate group

The hydrophobic tails are made up of fatty acids.

Question 8

What is the function of phospholipids in cells?

Answer 8

They form bilayers used to make membranes

This structure is crucial for cell compartmentalization.

Question 9

What is the biochemical test for lipids called?

Answer 9

Emulsion test

This test involves adding ethanol to dissolve lipids and then mixing with water.

Question 10

What happens during the emulsion test if lipids are present?

Answer 10

A white emulsion will form

This indicates the presence of lipids in the sample.

Question 11

Fill in the blank: A triglyceride contains _______ fatty acids.

Answer 11

three

This is in contrast to phospholipids, which contain two fatty acids.

Question 12

Fill in the blank: Phospholipids have a _______ head and _______ tails.

Answer 12

hydrophilic, hydrophobic

This dual nature is important for membrane formation.

Question 13

True or False: Both triglycerides and phospholipids contain glycerol.

Answer 13

True

Glycerol is a common component in both types of lipids.

Question 14

What is the role of triglycerides in the body?

Answer 14

Energy-storage molecules

They store energy for later use and are important for metabolism.

Question 15

How do phospholipids orient themselves in water?

Answer 15

Tails are as far away from the water as possible

This orientation leads to the formation of lipid bilayers.

Question 16

What type of bond is formed between glycerol and fatty acids in triglycerides?

Answer 16

Ester bonds

These bonds are crucial for lipid structure and function.

Question 17

What is a characteristic feature of unsaturated fatty acids?

Answer 17

Presence of carbon-carbon double bonds

This feature affects the physical properties of the fatty acids.

Question 18

what is a single bond refered too?

Answer 18

mono-unsaturated

Question 19

what does the hydrophobic part of phospholipids not consist of?

Answer 19

saturated or fatty acids

Question 20

what do the tails and heads of a phospholipid bilayer contain?

Answer 20

tails is fatty acid, head is phosphate

Question 21

why is the phospholipid bilayer polar?

Answer 21

due to its hydrophilic and hydrophobic regions

Question 22

what arent lipids soluble in?

Answer 22

acetone

Question 23

what letter is a hydrocarbon chain represented by?

Answer 23

R

Question 24

what are the state hydrolysed fatty acids are in ?

Answer 24

fluid and oily

Question 25

what are fats normally?

Answer 25

saturated and unsaturated and plasma at room temp

Question 26

how do you do the emulsion test?

Answer 26

1. first add food sample (crush if solid) 2. add ethanol and add equal volume of distilled water 3. shake the mixture