Test Date: _________
Name:________________
Study Guide Unit 4:
DNA / Mutations / Genetics
Quiz Dates: _______/_______
Period:________
Process of Discovery for DNA
Fill out the following table. Note contributions of the following scientists to the discovery of DNA & its structure:
Scientist(s)
Discovery
Franklin
Chargaff
Watson & Crick
The Structure of DNA
The structure of DNA is described as a __________________ because it looks like a twisted ladder. The
arrangement of the ______________ determines the type of protein. (hint Oreo cookie)
Fill in the following chart on the structure of DNA:
Ladder Sides
Ladder Rungs
Nucleotides are made of:
Which are connected by:
(name bond type)
Circle one nucleotide on this drawing.
Also label / color the following.
1. a phosphate - BLACK
2. a deoxyribose (sugar) - BLUE
3. a nitrogenous base – You decide
4. hydrogen bonds - GRAY
Fill in the complementary half of the following DNA strand:
side 1 - T-C -G-A- G- A- T- T- C- G- A- G- T
side 2
DNA Replication
DNA replication is the cell’s process of making an identical copy of its DNA during __________________, right
before it enters mitosis (or meiosis). The purpose it to make sure when the cell splits in two, both new cells
have the right amount of DNA.
-Fill in the blanks to the steps of DNA replication:
1. DNA replication begins with the enzyme _______________, which unzips the _______ bonds on DNA.
2. Complementary ______________ are added to both sides of the open DNA.
3. The final result is ________(#) helixes, each containing a ___________ strand & a _________ strand.
The Structure of RNA
RNA is another type of nucleic acid. Like DNA, it is made of a long chain of nucleotides. Fill in the differences
between RNA and DNA.
RNA
DNA
Mutations
Mutations are a change in the order of the ___________ of DNA. Things that can change or damage DNA is
known as a _____________. In the chart below describe the mutations:
Chromosomal Mutations
Insertion
Deletion
Substitution
Genetics: (answer the following questions on a different sheet of paper)
Round seed pods are dominant over wrinkled seed pods. The Punnett square below shows a cross
between parents with round and wrinkled seed pods. Use the following diagram to answer the next
three questions.
1. What is the phenotype of the offspring in block A? ________________
2. What is the genotype of the offspring in blocks B and D? _____________
3. What is the phenotype of the offspring in block C? ________________
4. Is it possible for an organism to have the phenotype that does not reflect the genotype? Hint…Mrs.
Phipps’s parents…..
5. In corn plants, green (G) is dominant to albino (g). What is the chance of a heterozygous cross
producing albino corn plants? ____________
6. When using Punnett squares to show inherited probability, we talk about dominant and recessive:
a. What is a dominant trait? How would you write it?
b. What is a recessive trait? How would you write it?
7. When two alleles for the same trait are different it is called _________________. When the two alleles
for one trait are identical it is called_________________.
8. Who is Gregor Mendel and what did he contribute to the study of genetics?
9. When purebred tall plants are crossed with hybrid tall plants, the offspring would be ______________.
10. What is a gene and where is it located?
11. What is the difference between codominance and incomplete dominance?
12. What is a mutation?