Transcript DNA to Eye Color? Just How does it Happen?

DNA to Eye Color?
Just How does it Happen?
Problem?
How do we go from DNA
to individual traits?
DNA acts as a blueprint
• DNA acts as a
blueprint for
making
proteins
• It is these
proteins that
give you your
hair and eye
color!
Gee- what do ribosomes do?
•
•
•
•
Make Proteins
Where are they?
Cytoplasm & RER
DNA- the “recipe” for
making proteins is
located in the nucleus
• HOW DO WE GET
FROM NUCLEUS TO
CYTOPLASM?
DNA to RNA?
• The instructions
for assembling
proteins are
“transferred”
from DNA to
RNA, which is
the second
type of nucleic
acid.
DNA vs. RNA
• Single Chain of
nucleotides
• Sugar is Ribose
• Uracil instead of
thymine
–Complimentary
to adenine
Transcription
• Transferring
information from
DNA to RNA is
called transcription
• Same as
replication, except
Adenine will pair
with Uracil
–Fill in the strand
RNA Does the GRUNT WORK!
• After TranscriptionRNA goes to the
cytoplasm to find a
Ribosome to make
proteins
• 3 types of RNA to do
this work!!
• mRNA
• tRNA
• rRNA
THE RNA’s
• mRNA (messenger)
– Carries transcribed
DNA code to ribosome
• tRNA (transfer)
– Brings amino acids to
ribosome in correct
order
• rRNA
– w/ other proteins
makes up structure of
ribosome
CHECKPOINT- Fill it in!!!!
DNA
• Double Helix
• Adenine
• Guanine
• Cytosine
• Thymine
• Deoxyribose
RNA
• Single Strand
• Adenine
• Guanine
• Cytosine
• Uracil
• Ribose
CHECKPOINT 2
• mRNA
• tRNA
• rRNA
• Carries transcribed
DNA code to
ribosome
• Brings amino acids
to the Ribosome
• Assists in ribosome
structure
FINALLY! RNA to Proteins
First, ya gotta understand
how the genetic code works!
Humans vs. Hard Drives
• DNA stores info in the form of
long sequences of bases
• 30,000 genes in humans
–3 billion base pairs
• Base pairs make up code for
amino acid sequence, which
make up the protein.
•A 3 base code in DNA or mRNA
is called a codon.
Each codon translates to a
particular amino acid.
•20 amino acids make up all
proteins for life
•Since codons are 3 bases, there
are 64 different codon sequences
-Some amino acids have two or
more codons.
These Codons are used by all living
things; thus, showing the unity of life on
Earth
Protein Synthesis
• 1) TranscriptionDNA is
transcribed into
mRNA in the
nucleus
• 2) mRNA moves
into the cytoplasm
and attaches to a
ribosome
Protein Synthesis (continued)
• 3) Translation- the
ribosome reads the
codon and matches it
with its anticodon
carried by the
tRNA’s in the
cytoplasm. Attached
to these anticodons
are the amino acids
that will be built into a
protein
Protein Synthesis (continued)
• 4) ElongationRibosome will continue
to build proteins one
amino acid at a time.
During this time, tRNAs
continue to bring the
corresponding amino
acids until ribosome
enters a “STOP” codon.
– Ribosome falls off
mRNA and protein
ready for use
Now…Let’s practice