Question 1

Which property of carbon is primarily responsible for the diversity of organic molecules found in living organisms?

Accepted Answer

Its ability to bond with four other atoms, allowing for large and complex molecules

Question 2

Isomers are molecules that:

Accepted Answer

Have the same molecular formula but different structures

Question 3

Which of the following best describes a hydrocarbon?

Accepted Answer

A molecule composed only of carbon and hydrogen atoms

Question 4

Which functional group is found in all amino acids and is responsible for their acidic properties?

Accepted Answer

Carboxyl group ($-COOH$)

Question 5

What type of reaction links monomers together to form polymers in biological systems?

Accepted Answer

Dehydration reaction

Question 6

During digestion, the proteins in cheese are broken down into amino acids. Which process is responsible for this breakdown?

Accepted Answer

Hydrolysis

Question 7

A monosaccharide with three carbons would have which of the following chemical formulas?

Accepted Answer

$C_3H_6O_3$

Question 8

Which of the following statements correctly compares starch and cellulose?

Accepted Answer

Starch is a storage polysaccharide in plants, while cellulose is a structural polysaccharide in plant cell walls

Question 9

Which of the following best explains why unsaturated fats are typically liquid at room temperature while saturated fats are solid?

Accepted Answer

Unsaturated fats have double bonds that create kinks, preventing tight packing

Question 10

Phospholipids are essential components of cell membranes. Which structural feature distinguishes them from fats (triglycerides)?

Accepted Answer

Phospholipids have two fatty acid tails and a phosphate group, while fats have three fatty acid tails

Question 11

Why are both fats and steroids classified as lipids, even though their structures are very different?

Accepted Answer

Both are hydrophobic and insoluble in water

Question 12

Which level of protein structure is directly determined by the sequence of amino acids in a polypeptide chain?

Accepted Answer

Primary structure

Question 13

A protein is denatured when it loses its specific shape and function. Which of the following could cause denaturation?

Accepted Answer

A change in temperature or pH

Question 14

Which of the following is NOT a function of proteins in living organisms?

Accepted Answer

Storing genetic information

Question 15

Which of the following statements about nucleic acids is correct?

Accepted Answer

DNA is a double helix, while RNA is usually single-stranded

Question 16

Which of the following best describes the structure of a nucleotide?

Accepted Answer

A sugar, a phosphate group, and a nitrogenous base

Question 17

Which process is responsible for the formation of peptide bonds between amino acids?

Accepted Answer

Dehydration reaction

Question 18

A mutation changes a single amino acid in the primary structure of a protein. Which level(s) of protein structure could be affected as a result?

Accepted Answer

All levels: primary, secondary, tertiary, and quaternary

Question 19

Which of the following best explains why enzymes are necessary for hydrolysis and dehydration reactions in cells?

Accepted Answer

Enzymes speed up the reactions by lowering the activation energy

Question 20

Which of the following is a correct real-life application of the concepts of macromolecules and their monomers?

Accepted Answer

When you eat bread, enzymes in your digestive system break down starch (a polysaccharide) into glucose (a monosaccharide) through hydrolysis

Chapter 3: Big Ideas – Introduction to Organic Compounds

Study Guide - Practice Questions