Question 1

Which property of carbon allows it to form a large variety of complex molecules essential for life?

Accepted Answer

Its four valence electrons, allowing it to form four covalent bonds

Question 2

Stanley Miller's 1953 experiment demonstrated that organic molecules could be synthesized under conditions thought to resemble those of early Earth. Which of the following best explains the significance of this experiment?

Accepted Answer

It showed that simple inorganic molecules could be converted into complex organic molecules abiotically

Question 3

Which of the following best describes a structural isomer?

Accepted Answer

Compounds with the same molecular formula but different covalent arrangements of their atoms

Question 4

A pharmaceutical company is developing a new drug. Why must they consider the enantiomers of the drug molecule?

Accepted Answer

Only one enantiomer may be biologically active, while the other could be ineffective or harmful

Question 5

Which functional group is responsible for the acidic properties of acetic acid, and what is its general structure?

Accepted Answer

Carboxyl group; $—COOH$

Question 6

Which of the following molecules contains a carbon atom with a tetrahedral geometry?

Accepted Answer

Methane ($CH_4$)

Question 7

Which functional group is found in ATP and is critical for its role in energy transfer within cells?

Accepted Answer

Phosphate group ($—OPO_3^{2-}$)

Question 8

A molecule with the formula $C_5H_{12}$ can exist as both pentane and 2-methylbutane. What type of isomerism does this illustrate?

Accepted Answer

Structural isomerism

Question 9

Which of the following statements about hydrocarbons is correct?

Accepted Answer

They consist only of carbon and hydrogen atoms

Question 10

Which functional group can form a 'cross-link' that stabilizes protein structure, and what is its chemical formula?

Accepted Answer

Sulfhydryl group; $—SH$

Question 11

Which of the following best explains why carbon dioxide ($CO_2$) is considered an inorganic molecule, despite containing carbon?

Accepted Answer

It lacks hydrogen atoms bonded to carbon

Question 12

Which of the following best describes a cis-trans (geometric) isomer?

Accepted Answer

Compounds with the same covalent bonds but different spatial arrangements around a double bond

Question 13

A molecule contains both a carboxyl group ($—COOH$) and an amino group ($—NH_2$). Which class of biological molecules does it most likely belong to?

Accepted Answer

Amino acids

Question 14

Which of the following functional groups is most likely to make a molecule more hydrophilic and able to form hydrogen bonds with water?

Accepted Answer

Hydroxyl group ($—OH$)

Question 15

Which of the following best describes the reaction that occurs when ATP reacts with water?

Accepted Answer

ATP is hydrolyzed to ADP and inorganic phosphate, releasing energy

Question 16

Which of the following is a real-world example of the importance of functional groups in biological molecules?

Accepted Answer

Estradiol and testosterone differ only in their functional groups, leading to different biological effects

Question 17

A molecule with the formula $C_2H_4$ has a double bond between its carbon atoms. What is the geometry around each carbon atom in this molecule?

Accepted Answer

Planar (trigonal planar)

Question 18

Which of the following statements about methyl groups ($—CH_3$) is correct?

Accepted Answer

They are nonpolar and can affect gene expression when attached to DNA

Question 19

Which of the following best explains why hydrocarbons are a major source of energy in biological systems?

Accepted Answer

Their carbon-hydrogen bonds store a large amount of potential energy that can be released during reactions

Question 20

A researcher discovers a new organic molecule with the following structure: $CH_3CH_2CH_2OH$. Which functional group is present, and what is the compound's likely classification?

Accepted Answer

Hydroxyl group; alcohol

Chapter 4: Carbon and the Molecular Diversity of Life – Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards