Chapter 4
Carbon and the Molecular Diversity of Life
Overview: Carbon: The Backbone of Life
• Although cells are _____________________ water, the rest consists mostly of carbon-based compounds
• Carbon is unparalleled in its ability to form ___________________________________________
______________________________________________________________________________
• Proteins, ____________________________________, carbohydrates, and other molecules that distinguish living matter are all composed of carbon compounds
Concept 4.1: Organic chemistry is the study of carbon compounds
• ___________________________________________ is the study of compounds that contain carbon
• Organic compounds range from simple molecules to colossal ones
• Most organic compounds contain ________________________ atoms in addition to carbon atoms
Concept 4.2: Carbon atoms can form diverse molecules by bonding to four other atoms
• ________________________________________________ is the key to an atom’s characteristics
• Electron configuration determines the kinds and number of bonds an atom will form with other atoms
The Formation of Bonds with Carbon
• With four valence electrons, carbon can form ________________ covalent bonds with a variety of atoms
• This ______________________________________ makes large, complex molecules possible
• In molecules with multiple carbons, each carbon bonded to four other atoms has a ___________________________________________shape
• However, when two carbon atoms are joined by a double bond, the molecule has a __________ shape
• The electron configuration of carbon gives it covalent __________________________________ with many different elements
• The valences of carbon and its most frequent partners (hydrogen, oxygen, and nitrogen) are the ______________________________________ that governs the architecture of living molecules
• Carbon atoms can partner with atoms other than hydrogen; for example:
• Carbon dioxide: CO2
• Urea: CO(NH2)2
Molecular Diversity Arising from Carbon Skeleton Variation
• Carbon chains form the skeletons of most organic molecules
• Carbon chains vary in length and shape
Hydrocarbons
• __________________________________ are organic molecules consisting of only carbon and hydrogen
• Many organic molecules, such as _______________, have hydrocarbon components
• Hydrocarbons can undergo reactions that release a large amount of ___________________
Isomers
• ________________________ are compounds with the same molecular formula but different structures and properties:
• ____________________________________________________ have different covalent arrangements of their atoms
• _____________________________________________________ have the same covalent arrangements but differ in spatial arrangements
• ___________________________________ are isomers that are mirror images of each other
• Enantiomers are important in the pharmaceutical industry
• Two enantiomers of a drug may have different effects
• Differing effects of enantiomers demonstrate that organisms are sensitive to even subtle __________________________________ in molecules
Concept 4.3: A small number of chemical groups are key to the functioning of biological molecules
• Distinctive properties of organic molecules depend not only on the carbon skeleton but also on the _______________________________________________________________ attached to it
• A number of characteristic groups are often attached to skeletons of organic molecules
The Chemical Groups Most Important in the Processes of Life
• _______________________________________________ are the components of organic molecules that are most commonly involved in chemical reactions
• The number and _________________________________ of functional groups give each molecule its unique properties
• The seven functional groups that are most important in the chemistry of life:
• ______________________________________________
• ______________________________________________
• ______________________________________________
• ______________________________________________
• ______________________________________________
• ______________________________________________
• ______________________________________________
ATP: An Important Source of Energy for Cellular Processes
• One phosphate molecule, _____________________________________________________ , is the primary energy-transferring molecule in the cell
• _________________ consists of an organic molecule called adenosine attached to a string of three phosphate groups