Download DNA and Protein Synthesis

DNA and Protein Synthesis
Chapter 11
DNA Structure & Function p58- video
Warm up: write down 1 thing you learned
from the video.
 DNA are complex molecules that hold all of
our genetic information.
 DNA are made up of long chains of
Nucleotides
 Each nucleotide is made of a sugar,
phosphate, and a nitrogen base.
 The nitrogen bases include: Adenine,
Guanine, Cytosine, and Thymine.
 Draw and label figure 11.1 (c) on p. 282 on
your left page of your notebook (1/3page)

Shape of DNA p58 video
It has a double helix shape, like a
zipper that is twisted
 The sugars and phosphates form the
backbone of the strand and the bases
pair up in the middle, like a ladder.
 The base pairs are always: G-C & A-T
 video
 Answer questions #1-3 in problem
solving lab11.1 on p283 on middle left
page

Questions p 57
1.
2.
3.
4.
How are purines different from
pyrimides?(top of 282)
What 3 substances make up a
nucleotide?
Compare how DNA is like a ladder.
Finish the other side of the DNA with
the correct base:
CATGACGT-
DNA Replication p60
Warm up: what part of the cell cycle does the
DNA double?
 Here’s how: video
 In the nucleus, the DNA is unzipped, making
2 strands.
 Nucleotides from the surroundings are
brought in to pair with each strand.
 The 2 new strands are exactly like the
original DNA.
 Animation:
 http://www.hhmi.org/biointeractive/dnareplication-basic-detail

From Genes to Protein p62
Warm up: discuss genetic engineering with
your group. What are pros and cons?
 The sequence of nucleotides in the DNA is a
code for making proteins.
 Every 3 nucleotides codes for a certain
amino acid. See chart p.292
 Questions: top of p 61
 What is UUU?
 CCG? AGG? UAA? GCG?

Chains of amino acids make up
proteins.
 Proteins in our body make us who we
are and keeps all of our systems
working.
 A gene is a segment of DNA that codes
for a particular protein.
 Middle of page 61: fill in concept map.

3 of these
code for
Large chains
make
This is coded
by a
DNA and RNA p62
DNA: Deoxyribo-Nucleic Acid
 RNA: Ribo-Nucleic Acid
 RNA is a single strand and DNA is double
stranded
 The sugar in RNA is Ribose and it is
Deoxyribose in DNA
 Both have 4 nitrogen base pairs: Guanine,
Adenine, Cytosine. But RNA has Uracil
instead of Thymine.
 DNA base pairs:
G-C & A-T
 RNA base pairs:
G-C & A-U
 Describe how DNA and RNA are different on

Transcription: copying DNA to RNA
inside the nucleus p64 video
Warm up: where are the directions for
making proteins stored? Where are they
made?
 In the nucleus, the DNA is unzipped and
certain genes are copied. This copy is
called messenger RNA.
 It is the exact opposite of the DNA it copied
and remember Uracil takes the place of
Thymine. Let’s try p 63!

Transcription practice p 63
Make RNA from the given DNA:
DNA
mRNA
DNA
mRNA
C
T
G
A
G
A
T
G
T
G
A
T

Translation: when mRNA is used to
make a protein p64
Then, mRNA goes to the ribosomes in
cytoplasm where the protein is made.
 mRNA attaches to ribosome
 Every 3 base pairs on mRNA is called a
codon
 transferRNA (tRNA) have an anticodon and
an amino acid attached to them.
 They bring in amino acids to the ribosome
and the chains are linked together to make
the protein.

Finally, the mRNA breaks apart and
returns to the nucleus to be reused
later. video
 Minilab p293 on bottom half of left side

Mutations: changes in DNA
sequences p66 video

Warm up:are all mutations bad? Why or why
not?

video

Exposure to radiation, viruses, and errors
during DNA replication, transcription or
translation can cause mutations.
Mutations can also be passed on to offspring
from parents.
Point mutation: a single base pair is incorrect
and it changes only one amino acid. Most
common type.


Frameshift mutation: a base is added or
deleted from amino acid. This changes
all the amino acids in the protein.
 Compare Point and Frameshift
mutations on the top of left page. Use
fig 11.11 p298 for reference.
 Chromosomal mutations: where parts
of a chromosome are broken and lost
or rejoined incorrectly. video
 Compare the 4 Chromosomal
mutations on the bottom of your left
page. Use fig 11.12 p300 for reference.
