Sugars and Lipids

Question 1

There are always two functional groups in sugar- what are they?

Answer 1

One carbonyl and multiple hydroxyl

Question 2

What is the difference between Aldose and Ketose?

Answer 2

Aldose has carbonyl at the end of the chain

Ketose has a carbonyl in the middle of its chain

Question 3

What is a common example of optical isomers?

Answer 3

Glucose (OH across) and Galactose (OH on same side)

Question 4

What are the two types of glucose isomers? Which is more stable?

Answer 4

Alpha glucose and Beta glucose

Beta glucose is more symmetrical, better for H bonding and more stable

Question 5

Sort maltose, starch, glycogen, cellulose and cellobiose into A glucose and B glucose

Answer 5

A glucose- maltose, starch, glycogen

B glucose- cellulose and cellobiose

Question 6

What 7 big roles do lipids play?

Answer 6

• Thermal Insulation
• Hormones and Vitamins
• Energy Storage
• Electrical insulation
• Water repellency
• Cell membranes
• Capture of light energy

Question 7

What is the composition of fats?

Answer 7

3 fatty acids and one glycerol connected by covalent bonds

Question 8

What is the composition of a fatty acid? What is one of their main characteristics?

Answer 8

A carboxyl group and one long hydrocarbon chain

They are amphiphilic

Question 9

Compare fats to starches

Answer 9

Fats contain more energy than starches but it takes longer to mobilize

Question 10

How do phospholipids move through a lipid bilayer

Answer 10

Phospholipids are in constant lateral motion. Rarely flip orientation

Question 11

How do double or single bonds of the fatty acid affect the permeability of a phospholipid membrane?

Answer 11

Double bonds cause kinks in the membrane (unsatured fatty acids)
This causes higher permeability!