Download Name: Date: Subject: DNA – Structure and Function Objectives

Name:
Date:
Subject:
DNA – Structure and Function
Objectives
Objective 1: ASWBAT describe the function and shape of a DNA molecule.
Objective 2: ASWBAT name the four nucleotides that make up DNA molecules.
Objective 3: ASWBAT name what nucleotides group together to make base pairs.
Objective 4: ASWBAT describe Chargaff’s Rule.
On a scale of 1 – 3 how well can you meet this objective now.
Objective: 1
Objective: 2
Objective: 3
Objective: 4
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Key Vocabulary Words
On a scale of 1 – 3 rate how well you know the vocabulary words below.
DNA
Nucleotide
Base Pairs
Adenine
Thymine
Cytosine
Guanine
Chargaff’s Rule
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Pre-quiz
1. What is a gene?
Answer:
2. What is a trait?
Answer:
3. How are traits and genes connected?
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4. Where do you find the DNA inside of your cells?
Answer:
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DNA Function
DNA is an essential molecule for life. It acts like a recipe holding the instructions telling
our bodies how to develop and function. DNA stands for deoxyribonucleic acid. It is
special, because DNA holds the code for every cell in your body. Every cell in your body
uses DNA as an instruction manual. DNA tells the cells how to make proteins that your
body uses to function and grow. You can think of like computer code, but only for your
cells not your computer.
DNA Structure
So, you get all of those nucleotides in two long chains that twist around each other. DNA
molecules look like a twisted ladder. DNA’s twisting shape is called a double helix.
1. What is the function of DNA?
Answer:
2. Describe the shape of a DNA molecule.
Answer:
Nucleotides
Although it may look complicated, the DNA in a cell is really just a pattern made up of four
different parts called nucleotides. Nucleotides are the building blocks of a DNA molecule.
Imagine a set of blocks that has only four shapes, or an alphabet that has only four letters.
DNA is a long string of these blocks or letters.
Nucleotides are the letters of the code that DNA uses to tell a cell what to do. The four
bases in DNA's alphabet are:
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Adenine (A)
Cytosine(C)
Guanine (G)
Thymine (T)
Nucleotides are represented by their first letter.
1. What is a nucleotide?
Answer:
2. What are the names of the four nucleotides that make up a DNA molecule?
Base Pairs
Nucleotides always pair up the same way.
 Thymine always pairs with Adenine and vice versa.
 Guanine always pairs with Cytosine and vice versa.
1. Name the nucleotide that pairs with each of the following.
Thymine
Guanine
Adenine
Cytosine
Chargaff’s Rule
In any sample of DNA, two things are always true.
 The amount of Adenine is always equal to the amount of Thymine.
 The amount of Cytosine is always equal to the amount of Guanine.
1. Chargaff’s rule states what two things about DNA?
Video: DNA Structure and Function
Quiz
Directions: Answer the following questions to see if you met the objectives.
1. What is the function of DNA?
Answer:
2. Describe the shape of a DNA molecule.
Answer:
3. What is a nucleotide?
Answer:
4. What are the names of the four nucleotides that make up a DNA molecule?
5. Name the nucleotide that pairs with each of the following.
Thymine
Guanine
Adenine
Cytosine
6. Describe the two parts of Chargaff’s rule.
7. Type the letter to complete the other side the DNA/gene below.
A
G
G
C
T
T
A
C
G