Question of the Day
4-19
1. DNA replication and
transcription occur in the _______,
while translation occurs in the
_______.
REVIEW
1. The 3 parts of a nucleotide = …
2. Cytosine pairs with _____ in DNA.
3. Monomer of a protein =
REVIEW
 Peptide
Bond –
–Covalent bond (sharing electrons)
formed between two amino acids
What holds nitrogenous bases
together?
– hydrogen bonds
DNA
REVIEW
The process of copying DNA = …
– DNA replication
Enzyme that breaks hydrogen
bonds between nitrogenous
bases = …
Enzyme that adds nucleotides to
form a new strand of DNA = …
REVIEW
Helicase –
REVIEW
 Replication
Fork –
–location where the DNA is splitting apart
Question of the Day
4-20
1. Transcription makes ________
from DNA and then _________
makes proteins from _________.
Announcement
4-20
Unit # 8 Test will NOT be Friday
4-29 but sometime the
following week!
Assignments
4-20
Skim (read over) section 10.3 and
complete questions #s 1-8 at the
bottom of page 202 – my.hrw.com. –
due NOW
Webquest – DNA Transcription and
Translation – due NOW
What is a codon?
Codon = Three nitrogen bases that code
for an amino acid
 There are “start” and “stop” codons
 The code is the exact same as in humans
as in a virus or a skunk
 Scientist see this as evidence that we all
share a common ancestor
Practice:
 What is UUU?
 What is the start codon?
Practice:
What is UGA?
What are the stop
codons?
Translation – Step by Step
A ribosome attaches
to the mRNA strand
and tRNA molecules
bring specific amino
acids to the ribosome.
Translation – Step by Step
AUG (methionine) signals
the start of protein
synthesis.
Translation – Step by Step
tRNA molecules continue along the
mRNA strand bringing with them the
corresponding amino acids. The
amino acids are connected by
peptide bonds
Translation
– Step by
Step
After the peptide bond is formed, the
ribosome slides along to the next
codon. The tRNA no longer carrying an
amino acid is released, and a new tRNA
carrying another amino acid can attach.
Translation – Step by Step
A chain of amino acids is
formed until a stop codon is
reached on the mRNA
strand.
Translation Summary
DNA SONGS:
http://www.youtube.com/watch?v=d1UPf7lXeO8
http://www.youtube.com/watch?v=FUA6_Ucw3i4
Question of the Day
1. What is a codon? Where
is it found?
4-26
2. What is an anticodon? Where is it
found?
Announcement
4-26
Unit # 8 Test will be Tuesday
5-3!
Transcription and Translation
Assignments
4-26
Handout with book assignment at
the end – due Thursday 4-28
Assignment
4-18
Handout
Skim (read over) section 10.3 and
complete questions #s 1-8 at the
bottom of page 202 – my.hrw.com.
A ribosome attaches to
the mRNA strand and
tRNA molecules bring
specific amino acids to
the ribosome.
A ______________ attaches
to the mRNA strand and
_______________________
bring specific amino acids to
the ribosome.
_________ (_______________)
signals the start of protein
synthesis.
AUG (methionine) signals
the start of protein
synthesis.
______________________________________
______________________ bringing with them
the corresponding amino acids. The amino
acids are connected by ___________________
tRNA molecules continue along the
mRNA strand bringing with them the
corresponding amino acids. The amino
acids are connected by peptide bonds
After the peptide bond is formed, the
After the peptide bond is formed, ________
ribosome slides along to the next
____________________________________.
codon. The tRNA no longer carrying an
The tRNA no longer carrying an amino acid
amino acid is released, and a new tRNA
is released, and ______________________
carrying another amino acid can attach.
____________________________________.
A chain of amino acids is
formed until a stop codon is
reached on the mRNA strand.
A chain of amino acids is formed
until a ______________________
is reached on the mRNA strand.