dna and protein synthesis. protein synthesis it’s a process –dna -> rna -> amino acids...
TRANSCRIPT
RNA
• Sugar is Ribose NOT what…• Has nitrogen base Uracil
instead of Thymine– Also contains the other 3
bases…what are they?• Only single stranded
Three processes in this unit…
• 1. Replication (DNA DNA)• 2. Transcription (DNA mRNA)• 3. Translation (RNA Protein)
A. DNA Replication
1. Occurs in the nucleus prior to any cell division
2. Enzyme is used to “unzip” or “unwind” the DNAa. Forms a bubble at the origin site
DNA Replication (cont.)3. Another enzyme is used to build a
complementary strand of DNA from the template piece of original DNAa. Nitrogenous bases pair up
1. A – T
2. C - G
4. As a result, you create two identical strands of DNA
Let’s Practice
• Replicate the following strand of DNA using the correct nitrogenous bases:
ATCGGCTATTAGGCATATCCGACGGTC
TAGCCGATAATCCGTATAGGCTGCCAG
Transcription
• 1.) DNA strand unzips– The bonds between the nitrogen bases are broken– Initiated by RNA polymerase (enzyme) binding to
promoter site on DNA• 2.) A single strand of mRNA (messenger RNA) is
made– Pair up the bases
• A• T• C• G
The mRNA then travels from nucleus to cytoplasm
Where in the cell does transcription take place?
Cyt
oplasm
Mito
chond
ria
Nucl
eus
Golg
i Body
Vac
uole
0% 0% 0%0%
100%1. Cytoplasm
2. Mitochondria
3. Nucleus
4. Golgi Body
5. Vacuole
Any given segment of DNA has directions that make unique what?
Glu
cose
Pro
tein
s
Lip
ids
Blo
od cel
ls
0% 0%0%
100%1. Glucose
2. Proteins
3. Lipids
4. Blood cells
If a DNA strand has the following sequence of base pairs – A C T G G T C C A A , then the mRNA strand would have what sequence?
T G
A C
C A
G G
T T
A C
T G
G T
C C
A A
T G
U C
C U
G G
T T
U G
A C
C A
G G
U U
4%
96%
0%0%
1. T G A C C A G G T T
2. A C T G G T C C A A
3. T G U C C U G G T T
4. U G A C C A G G U U
Why is mRNA called messenger RNA?
• Because it carries the directions to make a protein to the ribosome like a message
Actually 3 types of RNA
• mRNA- messenger – Brings message from nucleus to ribosomes in
cytoplasm• rRNA- ribosomal
– Make up a ribosome• tRNA- transfer
– “transfers” amino acids from the cytoplasm to the ribosome to be added to the chain
The difference between RNA and DNA is what?
The
phosphat
es
The
sugar
s
The
nitrogen
bas
es
The
way
the
mon
ome.
..
0%
36%
82%73%
1. The phosphates
2. The sugars
3. The nitrogen bases
4. The way the monomer units bond
mRNA is synthesized in the nucleus and travels to the cytoplasm to meet up with which organelle?
Mito
chond
ria
Rib
osom
e
Golg
i Body
Lys
osom
e
Nucl
eus
0%
95%
5%0%0%
1. Mitochondria
2. Ribosome
3. Golgi Body
4. Lysosome
5. Nucleus
Translation
1. mRNA meets up with a ribosome…why??– Ribosomes are the site for protein production
2. tRNA molecules bring amino acids to ribosomes
3. An mRNA codon will pair with a tRNA anticodon– Codon: 3 Nitrogen base sequence in mRNA
that specifies a specific amino acid – Anticodon: 3 Nitrogen base sequence in
tRNA
Translation (cont.)
4. As tRNA’s are added, amino acids are bonded together and will be released as a fully functional protein.
That’s the process, Now how do you know what amino acids make up a particular protein
• We use an mRNA codon chart
Where in the cell does transcription, the first part of protein synthesis, take place?
Mito
chond
ria
Nucl
eus
Rib
osom
es
Cyt
oplasm
0% 0%0%0%
1. Mitochondria
2. Nucleus
3. Ribosomes
4. Cytoplasm
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28
DNA has the directions to make what?
Glu
cose
Nucl
eotid
es
Pro
tein
s
Mono
sacc
harid
es
0% 0%0%0%
1. Glucose
2. Nucleotides
3. Proteins
4. Monosaccharides
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28
After a strand of mRNA is made where does it go?
Rib
osom
e
Mito
chond
ria
Lys
osom
e
Vac
uole
0% 0%0%0%
1. Ribosome
2. Mitochondria
3. Lysosome
4. Vacuole
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28
Where in the cell does translation, the second part of protein synthesis, take place?
Mito
chond
ria
Nucl
eus
Golg
i body
Cyt
oplasm
0% 0%0%0%
1. Mitochondria
2. Nucleus
3. Golgi body
4. Cytoplasm
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28
Molecules called tRNA’s are floating around the cytoplasm carrying what?
mRNA’s
Glu
cose
DNA
Nucl
eotid
es
Am
ino A
cids
0% 0% 0%0%0%
1. mRNA’s
2. Glucose
3. DNA
4. Nucleotides
5. Amino Acids
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28
An mRNA codon is made up of how many nitrogen bases?
1 3 6 24
0% 0%0%0%
1. 1
2. 3
3. 6
4. 24
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28
Using your mRNA codon chart, what amino acid would a ribosome call for if the codon was A A C ?
Phen
ylal
anin
e
Glu
tam
ine
Asp
arag
ine
Lys
ine
Tyr
osine
0% 0% 0%0%0%
1. Phenylalanine
2. Glutamine
3. Asparagine
4. Lysine
5. Tyrosine
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28
What protein would be synthesized from the following mRNA strand?A C U U U C G A A U A C
Thre
onine
– phen
ylal
...
Phen
ylal
anin
e –
leuci
..
Tyr
osine
– glu
tam
ate.
.
Lys
ine
– cy
stei
ne –
a...
0% 0%0%0%
1. Threonine – phenylalanine – glutamate – tyrosine
2. Phenylalanine – leucine – methionine – valine
3. Tyrosine – glutamate – phenylalanine – threonine
4. Lysine – cysteine – arginine – histidine
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28
What protein would be synthesized from the following DNA segment?T A A G T A C G C T A G
Isole
ucine
– al
anin
e –.
..
Isole
ucine
– his
tidin
e ...
Phen
ylal
anin
e –
leuci
..
Isole
ucine
– le
ucin
e –.
..
0% 0%0%0%
1. Isoleucine – alanine – histidine – alanine
2. Isoleucine – histidine – alanine – isoleucine
3. Phenylalanine – leucine – valine – arginine
4. Isoleucine – leucine – threonine – lysine
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28