Lecture 4: Carbon And The Molecular Diversity Of Life

Question 1

Stanley Miller’s apparatus showed that

Answer 1

Complex molecules formed from simple molecules abiotically on early Earth

Question 2

Stanley Miller’s apparatus concluded

Answer 2

That chemical evolution occurs readily if simple molecules with high free energy are exposed to kinetic energy

Question 3

Electron configuration is the key to

Answer 3

An atom’s chemical characteristics. It determines the kinds and number of bonds an atom will form with other atoms

Question 4

Number of unpaired electrons in valence shell of an atom equals

Answer 4

An atom’s valence (number of covalent bonds it can form)

Question 5

Hydrocarbons are

Answer 5

Organic molecules consisting of only carbon and hydrogen

Question 6

Hydrocarbon structure

Answer 6

Hydrogen atoms attached to carbon skeleton wherever electrons are available for covalent bonding

Question 7

Many organic molecules (fats and carbohydrates) have

Answer 7

Hydrocarbon components

Question 8

Hydrocarbon characteristic

Answer 8

Hydrophobic compound due to nonpolar C-to-H bonds

Undergo reactions that release a large amount of energy

Question 9

Isomers are

Answer 9

Compounds with same molecular formula but different structures and properties

Question 10

Structural isomers have

Answer 10

Different covalent arrangements of their atoms

Question 11

Cis-trans isomers (geometric isomers) have

Answer 11

The same covalent bonds but differ in their spatial arrangements

Question 12

Enatiomers are isomers that

Answer 12

Are mirror images of each other

Question 13

C skeleton gives a molecule

Answer 13

It’s overall shape

Question 14

Distinctive properties of organic molecules depend on

Answer 14

C skeleton and chemical groups attached to it

Question 15

Chemical groups defines

Answer 15

Chemical behavior of a molecule

Types of reactions molecule participates in

Question 16

Chemical (Functional) groups are

Answer 16

Groups of atoms attached to C skeleton of organic molecules in a specific way

They “make things happen”

Question 17

Atoms that can be in a chemical group attached to carbon

Answer 17

Hydrogen, nitrogen, oxygen, phosphorus, sulfur

Question 18

Chemical groups are directly involved in

Answer 18

chemical reactions

Question 19

The number and arrangement of functional groups give

Answer 19

Each molecule unique properties

Determine how a molecule is going to behave

Question 20

Hydroxyl group

Answer 20

Act as weak acid, are polar molecules, forms h-bonds and are soluble in water

Question 21

Carbonyl structure

Answer 21

Ketones if the carbonyl group is within a carbon skeleton

Aldehydes if the carbonyl group is at the end of the carbon skeleton

Question 22

Carbonyl group

Answer 22

Site of reactions that link acetaldehyde and acetone molecules into larger, more complex organic molecules

Question 23

Carboxyl name of compounds

Answer 23

Carboxylic acids or organic acid

Question 24

Carboxyl group

Answer 24

Acts as an acid when in a solution; can donate an H+ because the covalent bond between oxygen and hydrogen is so polar

Question 25

Amino name of compound

Answer 25

Amines

Question 26

Amino group

Answer 26

Acts as a base when in solution

Question 27

Sulfhydryl name of compound

Answer 27

Thiols

Question 28

Sulfhydryl group

Answer 28

Consists of sulfur bonded to hydrogen Link one another via disulfide (S-S) bonds Hydrophobic

Question 29

Phosphate name of compound

Answer 29

Organic phosphates

Question 30

Phosphate group

Answer 30

Carry negative charges on 2 of their oxygen atoms Bonded together together store chemical energy used in chemical reactions

Question 31

Methyl compound name

Answer 31

Methylated compounds

Question 32

Methyl functional property

Answer 32

Addition of a methyl group to DNA, or to molecules bound to DNA, affects the expression of genes

Question 33

Hydroxyl functional properties

Answer 33

Is polar as a result of the electrons spending more time near the electronegative oxygen atom Can form hydrogen bonds with water molecules, helping dissolve organic compounds such as sugar

Question 34

Carbonyl functional properties

Answer 34

A ketone and an aldehyde may be structural isomers with different properties, as is the case for acetone and propanol Ketone and aldehyde groups are also found in sugars, giving rise to two major groups of sugars: ketoses (containing ketone groups) and aldoses (containing aldehyde groups).

Question 35

Carboxyl functional properties

Answer 35

Acts as an acid; can donate an H+ because the covalent bond between oxygen and hydrogen is so polar: found in cells in the ionized form with a charge of 1- and called a carboxylate ion.

Question 36

Amino functional properties

Answer 36

Acts as a base; can pick up an H+ from the surrounding solution (water, in living organisms): found in cells in the ionized form with a charge of 1+

Question 37

Sulfhydryl functional properties

Answer 37

Two Sulfhydryl groups can react, forming a covalent bond. This “cross-linking” helps stabilize protein structure Cross linking of cysteines in hair proteins maintains the curliness or straightness of hair. Straight hair can be “permanently curled” by shaping it around curlers and then breaking and re-forming the cross-linking bonds

Question 38

Phosphate functional properties

Answer 38

Contributes negative charge to the molecule of which it is a part (2-when at the end of a molecule, as at left; 1- when located internally in a chain of phosphates) Molecules containing phosphate groups have the potential to react with water, releasing energy

Question 39

ATP

Answer 39

Adenosine triphosphate stores the potential to react with water or other molecules. Reaction releases energy that can be used by cell