Download Gene Mutations

DNA, RNA, and Protein Synthesis Notes
Biology 5.0
Name:
Date:
Period:
Activating Prior Knowledge:
1. List the eight characteristics of living things.
2. List the five elements found in nucleic acids.
3. Name the monomer of nucleic acids.
4. Identify the three parts of the monomer mentioned in question three.
5. Name two examples of nucleic acids.
6. Identify two differences between prokaryotic and eukaryotic cells.
7. Which organelle serves as the site of protein synthesis?
8. Name the monomers of proteins.
9. Which organelle modifies, sorts, and packages proteins?
10. Which organelle serves as an intracellular highway?
1
The Structure of DNA
___________________________________ is a polymer formed from units called ________________
 Each nucleotide monomer is made of three parts:
a)
b)
c)
 There are four nitrogenous bases found in DNA:
A. Purines (2 ring nitrogen base)
a)
b)
B. Pyrimidines (single ring base)
a)
b)
 The DNA polymer looks like a twisted ladder, with the _________________ and __________________
making up the sides of the ladder and the _________________________ are the steps/rungs.
 Nitrogen bases pair according to certain rules:
a)
b)
 The nitrogen bases are held together by __________ bonds.
Check your Understanding:
DNA is a long molecule made up of units called nucleotides. Each
nucleotide is made up of three basic parts:
There are 4 kinds of ______________ in DNA.
They _______ according to two rules:
1) ____________ always pair with _______________ and
2) Guanine pairs with _________ and _________ pairs with adenine.
2
DNA Replication

Because each of the two strands of the
has all of the information to
reconstruct the other half, the strands are said to be ___________________________.

Each strand of the double helix of DNA serves as a ________________ to make the other strand.

For example, if one side of the DNA had the base sequence
A T C C G A T G A T T
The complementary strand would read as follows:
__________________________
 DNA replication is carried out by a series of ____________________
a) they separate ( ______________ ) the two strands of the
b) __________________________ adds new
 Illustrate the process of semi-conservative replication below (use colored pencils if possible):
3
RNA
____________________________________________________
 Consists of a long chain of macromolecules made up of _______________________
a)
b)
c)
 3 differences between DNA and RNA:
1)
2)
3)
 3 main types of RNA:
1)
2)
3)
__________________
__________________
__________________
4
RNA Synthesis: Transcription
__________________________________________________________________________________________

All 3 types of RNA are synthesized from ________ in the _________________ and then used to synthesize
___________________ in the ________________________.

Protein synthesis is a two step process:
1)
2)

___________ must bring the genetic information from _______
in the nucleus to the _______________________ in the cytoplasm.

An enzyme, _______________________________ , attaches to the __________ molecule and separates the
______________________________.

The enzyme moves along the DNA molecule and synthesizes a ___________________ mRNA strand.
 Transcribe the given DNA sequence into a complementary mRNA:
A T G C A A G T C A T T C C A G C T
____________________________________________
 The process of
 The mRNA must be processed
takes place in the ______________________.
leaving the nucleus.
1)
________________ and ________________ are transcribed from
2)
________________ are cut ________ of the mRNA and ________________ are spliced back together
3)
A ______________ and a ______________ are added to the mRNA
5
 Introns:
 Exons:
Ribosomes and Protein Synthesis

The information that DNA transfers to
way in which the four nitrogenous
is in the form of a code, which is determined by the
are
in DNA.

DNA directs the formation of _____________________.

The monomers of proteins are _________________________.
o There are ______ different amino acids.
o A _________________ bond holds two amino acids together.
o A

molecule is removed when this bond forms -
The mRNA produced in the _______________ during ___________________ travels to the
__________________ to begin the process of _____________________.

Once at the ribosome, the mRNA is read ______ nucleotides at a time.
o A __________ is a combination of
sequential
nucleotides on _________

There are ________ different codons.

Each codon specifies a particular ____________________ that is to be placed in the polypeptide chain.
o ______ is the “initiator” codon.
o There are ______ “stop” codons.
6
Translation involves __________, __________, and _________.
o ______________________ carries the amino acids to the ribosome.
(different tRNA for each amino acid)
o ______________________ makes up the major part of the ribosome.

Three sequential nucleotides on a tRNA molecule are called an
___________________.

The anticodon on the ___________ is complementary to the codon of __________.
UAG CUG AAU CGC
AUC GAC UUA GCG AAU CAG GAU

Each codon & anticodon bind together, and a _________________ forms between the ______ amino acids.

The polypeptide chain continues to grow until the ribosome reaches a _________________________.
o A stop codon is a codon for which no __________ molecule exists.
o The ____________________ releases the newly formed
.
7
Mutations – Section 13.3
What is a mutation? When does a mutation occur?
Type of
Mutation
Germ Mutation
Somatic Mutation
Cell(s)
Affected
Impact
Types of Mutations
Gene Mutation
Chromosomal Mutation
Mutagens:

Chemical:

Physical:
Point Mutation
 Mutations that involve changes in
are known as
________________ mutations because they occur at a
 They generally occur during
point in the DNA sequence.
.
 If a gene in one cell is altered, the alteration can be
from the original one.
 A point mutation is a gene/chromosomal mutation (circle one).
 Point mutations include __________________________, _________________________, and
__________________________,
8
Gene Mutations
Type of Point
Mutation
Description

1) SUBSTITUTION


A) Silent
Mutation


A change in one base pair causes _________
____________________________________

The result is called “missense” since the
__________________________________

The effect of a missense mutation on the
_____________ is _____________________

Sickle Cell Anemia: __________________
_______________________________________
B) Missense
_______________________________________
Mutation
9
Type of Point
Mutation
Description

C) Nonsense
Mutation





2) INSERTION
OR DELETION


If a nucleotide is added or deleted, the bases
are still read in _______________________,  Deletion:
THE FAT CAT ATE THE RAT
but now those groupings __________ in
THE FAT ATA TET HER AT
every __________ that follows the mutation.
Also called _________________________
 Insertion:
THE FAT CAT ATE THE RAT
Frameshift mutations can change _________
THE FAT CAR TAT ETH ERA T
___________________ that follows the
point of the mutation and can alter a
_______________so much that it is unable
to perform its ________________ functions.
Muscular Dystrophy
Both Duchenne MD and Becker MD result from mutations of a gene on the
__________________________ that codes for the dystrophin protein in
______________ cells; this protein helps to stabilize the plasma membrane during the
mechanical stresses of muscle contraction.
o more common in ____________ than in ____________
10
DNA, RNA, and Protein Synthesis Review Questions
Day One
Day Three
Day Two
Day Four
11