Lecture 3

Question 1

Cell Composition

Answer 1

70-95% water
Carbon-based compounds
C–C bond
C bonded to other elements (H,O,N,S,P, carbs, lipids, proteins, DNA)

Question 2

Carbon Atoms

Answer 2

Building blocks of biological molecules
4 valence electrons
Can form 4 covalent bonds

Question 3

Chemical Groups

Answer 3

Study Card Deck
The properties of an organic molecule also depend on the chemical groups attached to the carbon skeleton
They replace one or more hydrogens of a hydrocarbon

Question 4

Carbon-based Molecules

Answer 4

Carbohydrates
Proteins
Nucleic Acids
Lipids - diverse group of hydrophobic molecules built from two or more different types of smaller subunits

Question 5

Dehydration

Answer 5

Synthesizes a polymer
Removes a water molecule so a new bond can form

Question 6

Hydrolysis

Answer 6

Breaks down a polymer
Adds a water molecule, breaking a bond

Question 7

Carbohydrates

Answer 7

Simplest Carbs are monosaccharides that vary in location and length of the carbonyl group and carbon skeleton, respectively
Serve as raw material for synthesis of other molecules including amino and fatty acids

Question 8

Monosaccharides

Answer 8

simplest form of sugar and the most basic unit from which all carbohydrates are built

Question 9

Disaccharides

Answer 9

2 monosaccharides joined by a covalent bond

Question 10

Polysaccharides

Answer 10

Polymers of 100s-1000s of monosaccharides
Function: Energy storage (starch in plants and glycogen in animals)
ie: Cellulose functions as a structural component

Question 11

Lipids

Answer 11

Hydrophobic (nonpolar C–H covalent bonds)
Three Forms: fats, phospholipids, and steroids

Question 12

Hydrogenated Fats

Answer 12

Synthetically converted to saturated fat by adding hydrogen, allowing them to solidify
Process can produce trans fats

Question 13

Fats

Answer 13

Glycerol combined with three fatty acid chains
Two forms: saturated fats (lard, butter) (no C=C double bonds) and no kinks so they can pack closer together and unsaturated fats (oils, margarine) (yes C=C double bonds) with kinks

Question 14

Polyunsaturated Fats

Answer 14

More than one unsaturated carbon bond
Typically liquid at room temp
Can reduce cholesterol levels in blood

Question 15

Trans Fats

Answer 15

Worst type of fat to eat
Can raise LDL (bad) cholesterol level and lower HDL (good) cholesterol level, increasing risk of heart disease

Question 16

Phospholipids

Answer 16

Consists of a hydrophilic head and hydrophobic tail
Contains glycerol, two fatty acids, a phosphate group, and choline

Question 17

Steroids

Answer 17

Carbon with 4 rings and varying functional group
Cholesterol: a component of the membrane and the precursor of all other steroids including testosterone and estrogen