AP Biology Summer Assignment Nucleic Acids and Proteins
Name_________________________________________
Nucleic Acids and Proteins
In this lesson you will learn how the structures of monomers determine the structures and functions of
macromolecules. In particular, this lesson focuses on the structures of DNA, RNA, and proteins and how their
molecular components interact with each other their environment. The concept of directionality will be introduced.
Lesson Objectives

Define a monomer and state its importance to the structure and functions of a polymer.

Recognize diagrams of DNA and RNA nucleotides, and relate the structure of the nucleotide monomers
to the structure and function of both nucleic acids.

Recognize the basic structure of an amino acid, tell how amino acids vary, and relate the structure of
amino acid monomers to the structure and function of proteins.

State how directionality of nucleic acids and proteins affects their function.
Questions
What is a monomers
What chemical reactions help to assemble polymers?
What are the 3 basic structures that make up DNA and RNA? Describe each.
What are the four basic structures of a protein?
What environmental variables can interfere with chemical bonds and cause proteins to denature?
AP Biology Summer Assignment Nucleic Acids and Proteins
Set the Stage
The function of all living things is indirectly governed by the genetic information encoded within DNA. The mystery
of how DNA encoding works started to become clear in 1953 when James Watson and Francis Crick determined
the structure of DNA with the aid of X-ray diffraction technology, mathematics, and ideas from other scientists.
They were able to determine how the subunits called nitrogenous bases were paired together in unlimited
combinations within the double-helical structure of DNA to provide the templates for life. Amino acids, the building
blocks of proteins, can also be combined in thousands of varieties to provide the gene-regulated components for
cells, tissues, organs, and organisms.
What might the consequences be for an organism if a nucleotide in DNA or an amino acid in a protein is
substituted or excluded in the transcription or translation process?
Write your response below.
Reading Guide
Read the Nucleic Acids & Proteins: Reading Assignment and take notes. Review the Keywords, describe the
Identifications, and answer the Essential Questions.
Keywords
Keyword
Definition/Notes
amino acid
the organic molecules from which proteins are made
dehydration synthesis
an enzymatic reaction that connects two monomers while creating a water
molecule
fatty acids
the organic molecules that serve as the units from which lipids are made
monomer
building block molecules for polymers
monosaccharides
the organic molecules that serve as the units from which carbohydrates are made
mRNA
messenger RNA: a linear RNA molecule that contains codons
nonpolar molecule
a molecule that lacks a dipole or permanent positive and negative areas
nucleotide
a subunit of a nucleic acid that consists of a phosphate group, a five-carbon
sugar, and a nitrogenous base
peptide bond
a chemical bond connecting two amino acids together with the carboxyl group of
one and the amino group of the other
polar molecule
a molecule in which there are positive and negative areas
polymer
large molecules of repeating groups of molecularly identical subunits
rRNA
ribosomal RNA: a type of RNA molecule that makes up the main part of the
structure of a ribosome
tRNA
transfer RNA: a type of RNA molecule that carries amino acids to the site of
protein synthesis in ribosomes
Identifications
Describe the Identifications. Use names, events, dates, and research articles to help describe the identification.
AP Biology Summer Assignment Nucleic Acids and Proteins
Identifications
Description/Notes
macromolecule
chemical bonding
DNA and RNA structure
protein structure and folding
protein structure and folding
Essential Questions
Answer the following questions from your reading:
1. What is a monomer, and what relation does it have to the structure and function of polymers?
2. How do nucleic acid monomers influence the function of DNA and RNA?
3. How does the sequence of an amino acid determine the three-dimensional structure of the protein?
4. What does directionality mean when referring to nucleic acids and proteins?
Free-Response
Amino Acid Sequence of Protein – Primary Structure
In a microbiology lab, scientists discover that joining together amino acids B and I forms a catalyst that initiates
enzymatic reactions within a muscle cell. They observe that these amino acids when in close proximity form an
active site that is able to engage and bind specifically to a substrate molecule. (a) Given the primary structure of
the protein in the figure, explain how it is possible for these two amino acids, that are distant in location, to work
together to form an active site for enzymatic reactions. (b) Justify your answer with a discussion of the chemical
interactions between monomers found in proteins.
Write your response below.
AP Biology Summer Assignment Nucleic Acids and Proteins
Extensions
1. Locate and read a few current event articles or watch a few videos about genetic engineering. How might
advances in the field of genetic engineering affect you now and in the future?
2. Find out how genetic testing is conducted. What are some ethical pros and cons to using this technology?
3. Explore genetic diseases. What are some explanations for why there are so many different genetic diseases?
Remember: At the completion of this lesson, save your Student Guide in your unit folder.
AP Biology Summer Assignment Nucleic Acids and Proteins
Information for Free Response
Essential Knowledge
4.A.1 The subcomponents of biological molecules and their sequence determine
the properties of that molecule.
Science Practice
6.1 The student can justify claims with evidence.
6.4 The student can make claims and predictions about natural phenomena
based on scientific theories and models.
Learning Objectives
4.3 The student is able to use models to predict and justify that changes in the
subcomponents of a biological polymer affect the functionality of the molecule.
Free-Response Scoring Guidelines
4 points maximum.
(Part a) Up to 3 points for the following correct explanations.
Effects may include:
 Proteins are unique macromolecules that are composed of several smaller monomers. These monomers,
amino acids, are linked together through the process of dehydration synthesis. Peptide bonds join amino
acids in the primary structure (as seen in Figure 1, while additional chemical interactions may join
adjacent or distant amino acids as they form secondary, tertiary, and quaternary structures.
 The chemical interactions of the R groups of the amino acids allow proteins to rearrange spontaneously
to form tertiary and quaternary structures. The order in which the amino acids are linked determines the
structure and the function of that protein.
 Although amino acids B and I are distant in its primary structure, chemical interactions between their
functional groups allows them to partner as an active site.
(Part b) 1 point for a correct justification of chemical interactions in proteins.
 The structural design of monomers relies on the chemical interactions of their functional groups. Chemical
bonds allow certain monomers to rearrange to form various structures. Common functional groups found
in amino acids are the amino group −NH2 and the carboxyl groups −COOH.The varying chemical
properties of these functional groups, according to how they are attached to the various carbon rings and
chains, are the reason that different monomers have unique characteristics that aid in protein function.