Transcript Nucleic Acids DNA & RNA

Nucleic Acids
DNA
and
RNA
• Organic molecules to
store genetic
information and transmit
genetic information for
future generations
DNA - DEOXYRIBONUCLEIC
ACID
• blueprint of life (has the
instructions for making
an organism’s proteins)
• established by James
Watson, Francis
Crick & Rosalind Franklin
• codes for your genes
• shape of a double helix
• made of repeating
subunits called
nucleotides
•Gene - a segment of DNA
that codes for a protein,
which in turn codes for a trait
(skin tone, eye color..etc), a
gene is a stretch of DNA.
• Nucleotide - consists
of a sugar, phosphate
and a base- A,G,T,C
Replication
Making new DNA from existing DNA.
Uses DNA base pairing
rules.
•Happens during the S phase of Interphase.
•Ensures each daughter cells is an exact copy
of the parent cell.
•Assisted by enzymes called DNA polmerase.
RNA - RIBONUCLEIC ACID
3 types ~mRNA, tRNA & rRNA
• RNA is similar to DNA except:
1. has one strand instead of two strands.
2. has uracil instead of thymine
3. has ribose instead of deoxyribose
Transcription & Translation
Transcription
is making the
mRNA to be
used in protein
synthesis
Translation
is the actual
synthesis of
the protein
needed to
build the
organism
Transcription
• Happens in the Nucleus
• Creates mRNA that can leave the nucleus
• Uses base pairing rules of:
A-U, T-A, C-G & G-C
Translation
RNA Reunion
• Happens at the ribosomes (in cytoplasm & the rough
ER).
• ALL 3 RNA types are involved.
• Uses 20 amino acids as the ingredients for EVERY
LIVING THING on our planet!!
• Actual synthesis of the polypeptide (protein)
Amino acids
1.Every 3 bases on
the mRNA is called
a codon.
2.Each codon is the
“code” for 1
particular amino
acid out of 20.
3.Amino acids are the
monomers of
proteins!
• Codon UUU is ____?
Codon GGG is ____ ?
Codon UGA is ____ ?
Codon AGT is ____ ?
PRACTICE!!
Page 303 in your book!
• DNA STRAND:
TAC TTC CGA GCG CCT CAT ACT
• mRNA Strand (transcription):
_______________________________
• Amino acid sequence (translation):
_________________________________
PRACTICE ANSWERS!!
• DNA STRAND:
TAC TTC CGA GCG CCT CAT ACT
• mRNA Strand (transcription):
AUG AAG GCU CGC GGA GUA UGA
• Amino acid sequence (translation):
Methionine-Lysine-Alanine-ArganineGlycine-Valine- STOP
mRNA is the
messenger
RNA that holds
the “recipe” to
put the protein
together.
tRNA
transfers the
correct amino
acid from the
cytoplasm to
the ribosome
rRNA physically makes up
part of the rbosomes – the
“factory” of protein
synthesis
polypeptide
Amino acid
tRNA
anti-codon
codon
mRNA
rRNA
(ribosome)
Nucleic Acid Processes
Mutations
ANY change in the DNA.
Chromosomal
Mutations involve
Duplication
chromsomes in part
or whole.
Inversion
Deletion
Translocation
Mutations
Substitution
Gene
mutations
Happen with
individual
nucleotides!
Frameshift
mutations are caused
by adding 1 nucleotide or
deleting 1 nucleotide.
Changes the “reading
frame” of the codons!!