Question 1

Which property of carbon most directly contributes to the diversity of organic molecules found in living organisms?

Accepted Answer

Its ability to form four covalent bonds with a variety of atoms

Question 2

Which of the following best describes a structural isomer?

Accepted Answer

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

Question 3

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

Accepted Answer

Enantiomers may have different effects in biological systems, with only one often being biologically active

Question 4

Which functional group is responsible for the acidic properties of acetic acid?

Accepted Answer

Carboxyl group ($$-\mathrm{COOH})$$

Question 5

A molecule with the formula $$C_6H_{12}O_6$ can exist as both glucose and fructose. What type of isomers are these?

Accepted Answer

Structural isomers

Question 6

Which of the following statements about hydrocarbons is correct?

Accepted Answer

They consist only of carbon and hydrogen atoms

Question 7

What is the significance of the phosphate group in ATP?

Accepted Answer

It stores potential energy that can be released during hydrolysis

Question 8

Which functional group is present in all amino acids and acts as a base?

Accepted Answer

Amino group ($$-\mathrm{NH}_2)$$

Question 9

Which of the following best explains why double bonds in carbon skeletons affect molecular shape?

Accepted Answer

Double bonds are rigid and prevent rotation, locking atoms in the same plane

Question 10

A fat molecule contains long hydrocarbon chains. What property do these chains confer to the fat molecule?

Accepted Answer

They make the molecule hydrophobic

Question 11

Which of the following molecules contains a carbonyl group?

Accepted Answer

Acetone ($$\mathrm{CH}_3\mathrm{COCH}_3)$$

Question 12

Which of the following best describes the difference between cis-trans (geometric) isomers?

Accepted Answer

They have the same covalent bonds but differ in spatial arrangement around a double bond

Question 13

Which functional group is most likely to be involved in energy transfer reactions in cells?

Accepted Answer

Phosphate group ($$-\mathrm{OPO}_3$$^{2-}$$)

Question 14

A molecule with both an amino group and a carboxyl group is classified as:

Accepted Answer

An amino acid

Question 15

Which of the following best explains why carbon is considered the backbone of life?

Accepted Answer

It can form large, complex, and diverse molecules by bonding to four other atoms

Question 16

Which of the following is a correct statement about the methyl group ($$-\mathrm{CH}_3$$)?

Accepted Answer

It is nonpolar and can affect gene expression when attached to DNA

Question 17

Which of the following best describes the role of functional groups in organic molecules?

Accepted Answer

They give molecules their unique chemical properties and reactivity

Question 18

Testosterone and estradiol are both steroids with a common carbon skeleton. What accounts for their different biological effects?

Accepted Answer

The different functional groups attached to the carbon skeleton

Question 19

Which of the following best explains why organisms are sensitive to subtle variations in molecular structure?

Accepted Answer

Small changes in structure, such as isomerism, can lead to significant differences in biological function

Question 20

A researcher is studying a molecule with the formula $$C_5H_{12}. $$She finds two different compounds with this formula: pentane and 2-methylbutane. What is the relationship between these two compounds?

Accepted Answer

They are structural isomers

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

Study Guide - Practice Questions

Study Guide - Flashcards