Transcript DNA & RNA - abdelbio

DNA & RNA
Protein Synthesis
DNA
http://www.youtu
be.com/watch?v
=4PKjF7OumYo
http://www.idigitalmotion.com/portfolio.htm
DNA vs RNA
Gene Expression
Protein Synthesis
C----G
T-----A
http://outreach.mcb.harvard.edu/animation
s/cellcycle.swf
Protein Synthesis
http://www.youtube.com/watch?v=1PSwhTGFMxs&feature=related
You have to read Chapter 10 to understand
the structure of DNA, RNA, DNA Replication,
and Transcription.
Use this as a sample checklist, to make sure
that you have all of the required elements. .
.
Model has:
_____ Phosphate Molecules (1)
_____ Pentose Sugar (1)
_____ Nitrogen Bases (A-T and G-C) (2)
_____ Hydrogen Bonds (1)
_____ Has at least 10 pairings (1)
_____ Clearly labeled legend (2 marks)
_____ Effort and Creativity (0 –1—2 )
TOTAL = 10
http://www.saskschools.ca/curr_content/bio
2030/bio30/unit1/dnaproject/activitytemplat
e/page4.htm
a. DNA - carries the blueprint for the order of amino acids to be
produced during protein synthesis.
b. Messenger RNA (mRNA) - copies the DNA molecule in the nucleus
during transcription and goes into the cytoplasm and attaches itself to a
ribosome. One 3 letter unit in an mRNA chain is called a codon.
c. Transfer RNA (tRNA) - drops off amino acids it is coded to carry at the
ribsome. The 3 letter code is complementary to mRNA and this 3 letter
code is called the anti-codon
d. Ribosome (rRNA) - this is where protein synthesis occurs. (Where the
protein is assembled)
Determine the amino acids coded for by a strand of DNA
1. Determining codons from a strand of DNA
Consider the following strand of DNA read from left to right:
TTATGCTCCTAA
When complementary base pairing occurs the following strand of mRNA
is obtained.
AAUACGAGGAUU
The codons are read three letters at a time from the transcribed mRNA.
The codons are:
AAU
ACG
AGG
AUU
2. Determining amino acids from mRNA codons
Find the codons in the table of mRNA codons below and the amino acids
they code for.
AAU -Asparagine ACG - Threonine AGG - Arginine AUU -isoleucine
5 steps in protein synthesis
-DNA serves as a code for proteins
-Transcription occurs. One strand of DNA serves as a template (blueprint)
for the formation of mRNA.
-after transcription, the newly formed mRNA goes into the cytoplasm and
attaches to a ribosomes.
-tRNA which carry specific amino acids, have anticodons which bind
complementarily with the mRNA codons
-The ribosome moves along the mRNA strand reading each codon. The
tRNA anticodon bonds to it complementary codon. The amino acid carried
by the tRNA is bonded to the polypeptide. The ribosome moves down the
mRNA strand one codon at a time releasing a tRNA as it does and making
room for another tRNA carrying an amino acid to join the mRNA.
DNA QUIZ QUESTIONS
RNA Transcription
http://wwwclass.unl.edu/biochem/gp2/m_biology/animation/gene/gene_a2.html
http://www.stolaf.edu/people/giannini/flashanimat/molgenetics/transcription.sw
f
Gene Expression:
DNA- Proteins
•Transcription = DNA → RNA
•Translation = RNA → protein
Genetic recombination
is a process by which a molecule of DNA is broken and then joined to a
different DNA molecule. Recombination can occur between similar molecules
of DNA, as in homologous recombination, or dissimilar molecules of DNA as in
non-homologous end joining. Recombination is a common method of DNA
repair in both bacteria and eukaryotes. In eukaryotes, recombination occurs in
meiosis as a way of facilitating chromosomal crossover. The crossover
process leads to offspring having different combinations of genes from their
parents
Genetic engineering, recombinant DNA technology, and gene
splicing are terms that apply to the direct manipulation of an organism's
genes.[1] Genetic engineering is different from traditional breeding, where
the organism's genes are manipulated indirectly. Genetic engineering
uses the techniques of molecular cloning and transformation to alter the
structure and characteristics of genes directly. Genetic engineering
techniques have been applied to various industries, principally medicine
and agriculture, with some success. Examples include production of
synthetic human insulin using modified bacteria.
Human genetic engineering can be used to treat genetic disease, but
there is a difference between treating the disease in an individual and
changing the genome that gets passed down to that person's
descendants
Recombinant DNA
Recombinant DNA (rDNA) is a form of DNA that does not exist naturally,
which is created by combining DNA sequences that would not normally occur
together.[1] In terms of genetic modification, recombinant DNA is introduced
through the addition of relevant DNA into an existing organismal DNA, such
as the plasmids of bacteria, to code for or alter different traits for a specific
purpose, such as antibiotic resistance.
A plasmid is a DNA molecule that is separate from, and can replicate
independently of, the chromosomal DNA.[1] They are double stranded and in
many cases, circular. Plasmids usually occur naturally in bacteria
A restriction enzyme (or restriction endonuclease) is an
enzyme that cuts double-stranded or single stranded DNA at
specific recognition nucleotide sequences known as restriction
sites.
http://www.obgynacademy.com/basicsciences/fetology/genetics/