Carbon and the Molecular Diversity of Life

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Slide 1

Carbon: The Backbone of Life

Although cells are 70–95% water, the rest consists mostly of carbon-based compounds

Carbon is unparalleled in its ability to form large, complex, and diverse molecules

Proteins, DNA, carbohydrates, and other molecules that distinguish living matter are all composed of carbon compounds

Slide 2

Fig. 4-1

Slide 3

Concept 4.1: Organic chemistry is the study of carbon compounds

Organic chemistry is the study of compounds that contain carbon

Organic compounds range from simple molecules to colossal ones

Most organic compounds contain hydrogen atoms in addition to carbon atoms

Slide 4

Vitalism, the idea that organic compounds arise only in organisms, was disproved when chemists synthesized these compounds

Mechanism is the view that all natural phenomena are governed by physical and chemical laws

Slide 5

Fig. 4-2

Water vapor

H2

NH3

“Atmosphere”

Electrode

Condenser

Cold

water

Cooled water

containing

organic

molecules

Sample for

chemical analysis

H2O

“sea”

EXPERIMENT

CH4

Slide 6

Concept 4.2: Carbon atoms can form diverse molecules by bonding to four other atoms

Electron configuration is the key to an atom’s characteristics

Electron configuration determines the kinds and number of bonds an atom will form with other atoms

Slide 7

The Formation of Bonds with Carbon

With four valence electrons, carbon can form four covalent bonds with a variety of atoms

This tetravalence makes large, complex molecules possible

In molecules with multiple carbons, each carbon bonded to four other atoms has a tetrahedral shape

However, when two carbon atoms are joined by a double bond, the molecule has a flat shape

Slide 8

Fig. 4-3

Name

Molecular Formula

Structural Formula

Ball-and-Stick

Model

Space-Filling

Model

(a) Methane

(b) Ethane

(c) Ethene

(ethylene)

Slide 9

The electron configuration of carbon gives it covalent compatibility with many different elements

The valences of carbon and its most frequent partners (hydrogen, oxygen, and nitrogen) are the “building code” that governs the architecture of living molecules