Title: Pearson Online Campbells Biology Excellent Website to help with online homework@ Post by: pickacu007 on Aug 29, 2011 Chapter 4: Carbon and the Molecular Diversity of Life
Chapter Quiz 1 . At the beginning of the 19th century, it was thought that the substances that made up living things were special and could not be synthesized by ordinary chemical methods. This now-discarded theory was called the theory of _____. (Concept 4.1) [Hint] special creation spontaneous generation vitalism materialism mechanism 2 . The first organic molecule to be synthesized from inorganic substances was _____. (Concept 4.1) [Hint] urea acetic acid ammonium cyanate insulin DNA 3 . Stanley Miller's experiments were significant because he demonstrated that _____. (Concept 4.1) [Hint] the behavior of any molecule containing a carbon atom was fundamentally the same under certain circumstances the theory of vitalism was valid a variety of simple organic compounds could be spontaneously synthesized from components in Earth's primitive atmosphere lightning discharges could produce the molecules previously presumed to have originated in volcanic outgassings urea could be synthesized from entirely naturally occurring salts 4 . Which is an organic molecule? (Concept 4.2) [Hint] Ne O2 CH4 NaCl H2O 5 . Which element is most particularly associated with organic chemistry? (Concept 4.2) [Hint] carbon sulfur nitrogen hydrogen oxygen 6 . What is the three-dimensional shape created by hybrid orbitals that are formed when a carbon atom is covalently bonded with four other atoms? (Concept 4.2) [Hint] a flat sheet with carbon in the center a triangle with carbon in the center a cube with carbon in the center a tetrahedron with carbon in the center All of the above are possible. 7 . A straight-chain carbon compound constructed from _____ must contain at least one carbon-carbon double bond. (Concept 4.2) [Hint] 6 hydrogen, 2 carbon 6 hydrogen, 3 carbon 6 hydrogen, 2 carbon, 1 oxygen 8 hydrogen, 3 carbon, 3 oxygen 14 hydrogen, 6 carbon 8 . Carbon atoms are the most versatile building blocks of the molecules used by living organisms because _____. (Concept 4.2) [Hint] carbon is the central atom of carbon dioxide, a necessary molecule for photosynthesis carbon is the central atom in urea, a molecule used by many living organisms to transport wastes from the body each carbon atom acts as an intersection point from which a molecule can branch off in up to four directions carbon can combine with hydrogen to form hydrocarbons all of the above 9 . The carbon atom is tetravalent; this means that _____. (Concept 4.2) [Hint] carbon readily forms ionic bonds carbon's first electron shell holds 4 electrons a carbon atom can complete its valence shell by forming four covalent bonds the bond angle between each bond is 90o, forming an arrangement like the points on a compass carbon has a total of 4 electrons 10 . A molecule has one carbon-carbon double bond and four monovalent atoms or groups. How many different geometric isomers exist for this molecule? (Concept 4.2) [Hint] none two four six eight 11 . The two compounds are related to each other by being _____. (Concept 4.2) [Hint] hydrocarbons organic compounds isomers double-bonded compounds all of the above 12 . Which of the following functional groups is present in all amino acids? (Concept 4.3) [Hint] -SH -COH -OH -NH2 -OPO3-2 13 . Which of these is found in all amino acids? (Concept 4.3) [Hint] -COOH -COH -OH -NH2 Both -COOH and -NH2 14 . Freon, CCl2F2, is _____ because _____. (Concept 4.2) [Hint] a structural isomer…there are several possible covalent arrangements a geometric isomer…free rotation about the bond axis is not possible an enantiomer…the carbon is asymmetric an enantiomer…the molecule exists in two mirror-image configurations not an isomer…there is only one structural configuration for the molecule 15 . Glucose and hexanoic acid each contain six carbon atoms, but they have completely different properties. Glucose is a nutrient found in food; hexanoic acid is poisonous. Their differences must be due to different _____. (Concept 4.3) [Hint] monomers macromolecules isomers quaternary structures functional groups 16 . Although the structures of the functional groups that are most important to life vary, they share one thing in common: They _____. (Concept 4.3) [Hint] all contain oxygen all have at least one double bond always cause the carbon to which they are attached to become an asymmetric carbon, thus they convert the molecule into an enantiomer all are hydrophilic and increase the organic compound's water solubility force straight chains of carbons into closed rings of carbon 17 . Ethanol, propanol, and methanol are three simple alcohols. They can be grouped together because they _____. (Concept 4.3) [Hint] all share the same functional group: a hydroxyl are soluble in water are hydrophobic all contain a carbonyl group increase the acidity of solutions 18 . Which one of the following molecules has a carboxyl functional group? (Concept 4.3) [Hint] R-NH2 R-COH R-COOH R-OPO3-2 R-SH 19 . Which one of the following molecules is a weak base? (Concept 4.3) [Hint] R-NH2 R-SH R-OH R-COOH none of the above 20 . Which of the following molecules is a weak acid? (Concept 4.3) [Hint] R-NH2 R-SH R-OH R-COOH none of the above 21 . Which one of the following functional groups increases the solubility of organic compounds in water? (Concept 4.3) [Hint] -SH -COOH -COH -NH2 all of the above 22 . Which of the following examples describes a unique functional property of the carboxyl group? (Concept 4.3) [Hint] Its compounds may be structural isomers with different properties. Two groups can interact to help stabilize protein structure. It is polar as a result of the electronegative oxygen atom drawing electrons toward itself. The covalent bond between oxygen and hydrogen is so polar that hydrogen ions tend to dissociate reversibly. It acts as a base. 23 . Which of the following functional groups is associated with a release of energy that cells can harvest to perform many functions? (Concept 4.3) [Hint] amino phosphate sulfhydryl hydroxyl carboxyl 24 . Which functional group would you predict is part of abscisic acid (ABA)? (Concept 4.3) [Hint] carboxyl hydroxyl carbonyl amino sulfhydryl 25 . The ionized or dissociated carboxyl group may be written as _____. (Concept 4.3) [Hint] -COOH -OH -COO- NH4+ -C=O 26 . Which one of the following groups would not be capable of hydrogen bonding with an oxygen atom on another functional group? (Concept 4.3) [Hint] amino hydroxyl carboxylic acid sulfhydryl none of the above 27 . Choose the pair of terms that complete this sentence about functional groups in organic chemistry: Carboxyl is to ______ as ______ is to base. (Concept 4.3) [Hint] acid…carbonyl sulfhydryl…carbonyl acid…amino hydroxyl…amino ketone…phosphate 28 . Which of these is a thiol? (Concept 4.3) [Hint] -SH -COH -OH -NH2 none of the above ©2005 Pearson Education, Inc., publishing as Benjamin Cummings Title: Re: Pearson Online Campbells Biology Excellent Website to help with online homework@ Post by: duddy on Aug 29, 2011 Do you need these answered?
Title: Re: Pearson Online Campbells Biology Excellent Website to help with online homework@ Post by: padre on Feb 18, 2014 27 . Choose the pair of terms that complete this sentence about functional groups in organic chemistry: Carboxyl is to ______ as ______ is to base. (Concept 4.3) [Hint] acid…carbonyl sulfhydryl…carbonyl acid…amino hydroxyl…amino ketone…phosphate acid ... amino ; A carboxyl group has acidic properties because it is a source of hydrogen ions. The hydroxyl group acts as a base because it can pick up a proton from the surrounding solution. Title: Re: Pearson Online Campbells Biology Excellent Website to help with online homework@ Post by: padre on Feb 18, 2014 26 . Which one of the following groups would not be capable of hydrogen bonding with an oxygen atom on another functional group? (Concept 4.3) [Hint] amino hydroxyl carboxylic acid sulfhydryl none of the above Methyl |