Lecture 5

Question 1

type of lipids

Answer 1

• fats and oils (energy storage)
• steroids (cholesterol)
• phospholipids (cell membranes)

Question 2

lipid

Answer 2

• non polar hydophobic compound
• consist of a long chains of hydrocarbons (C-H) (14-20)

Question 3

basic unit of lipids

Answer 3

fatty acid

Question 4

fatty acid

Answer 4

• nonpolar hydrocarbon chain (fatty) bonded to a carboxyl group (COOH: carboxylic acid)
• carboxyl bonds with hydroxyls of glycerol in an ester linkage

Question 5

triglycerides

Answer 5

• made of three fatty acids and 1 glycerol

Question 6

type of triglycerides

Answer 6

• fats and oils

Question 7

glycerol

Answer 7

• 3 OH groups (an alcohol)

Question 8

saturated fatty acids

Answer 8

• no double bonds between carbons
• saturated with hydrogen atoms
• max nb of H’s per C
• solid at room temperature

Question 9

monounsaturated fats

Answer 9

one double on in carbon chain

Question 10

unsaturated fats

Answer 10

• some doubles bonds in carbon chain
• liquid at room temperature

Question 11

polyunsaturated fats

Answer 11

more than one double bond in carbon chain

Question 12

types of saturated fats

Answer 12

• animal fats

Question 13

type of unsaturated fats

Answer 13

• plant fats

Question 14

steroids

Answer 14

• lipid molecules containing a complex of four carbon rings
• very important in structure of cell membranes & hormones determining sexual characteristics

Question 14

cell membranes

Answer 14

• made of molecules called phospholipids

Question 15

phospholipids

Answer 15

• don’t dissolve in water
• amphipathic: hydrophilic head and hydrophobic tail
• water molecules interact with the head but not the tail
• that drives the tails together

Question 16

in water, phospholipids don’t dissolve, they spontaneously form:

Answer 16

• micelles
• phospholipid bilayers (lipid bilayers)

Question 17

fluid mosaic model

Answer 17

proteins move around

Question 18

plasma membrane

Answer 18

• selective barrier that allows sufficient passage of oxygen, nutrients and waste to service the volume of every cell
• semi permeable

Question 19

general structure of plasma (biological) membrane

Answer 19

double layer of phospholipids

Question 20

what passes through the plasma membrane

Answer 20

• small non polar molecules
• small uncharged polar molecules

Question 21

what doesn’t pass through the plasma membrane

Answer 21

• large uncharged polar molecules
• ions