Transcript 1DNA - AHSbognasnc4m

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chromosomes: compact molecules of DNA
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A human set of chromosomes contains 23
pairs, half from mom, half from dad
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23rd pair are your
sex chromosomes
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Karyotype
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Genes are units of heredity that are passed on from parent to
offspring (two copies, one from each parent)
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Genes give specific instructions for proteins
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proteins give traits ex. widow’s peak, skin tone, etc
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Environment can be a factor in traits as well*
https://www.youtube.com/watch?v=ubq4eu_T
DFc
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Genome: All of our hereditary information. A
complete set of human gene instructions.
Gene: portion of DNA that codes for a
protein, ex. oncogene
the genome (and genes) is made of DNA
DNA
-DeoxyriboNucleic
Acid
-what chromosomes are made of
-the hereditary material inherited from
past generations, what chromosomes
are made of
-The vast majority ( >99%) of your
DNA is in the nucleus of your cells
1. DNA Structure
- double helix
- the sides of the ladder are made
of alternating deoxyribose sugar
and phosphate molecules
-the rungs of the ladder are made
of nucleotides held together by
hydrogen bonds
A-T
G-C
A always binds to T
C always binds to G
 DNA
 RNA  Protein
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very similar to DNA, but
◦ single stranded
◦ complementary base to adenine is not thymine, as
it is in DNA, but rather uracil.
A–U
G-C
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cellular machines
made from small units
called amino acids
carry out tasks, like
controlling the cell
cycle!
1.
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DNA  RNA
DNA (double stranded) is transcribed in the
NUCLEUS with the aid of an enzyme called
RNA polymerase.
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a) RNA polymerase unwinds and unlinks the
two strands of DNA.
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b) The TEMPLATE strand
will be used by RNA
polymerase.
RNA polymerase adds the
RNA base compliment to
the DNA template to
make the RNA
For example:
TACGGGAGTCTC
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The newly formed RNA strand is SINGLE
STRANDED.
It leaves the nucleus and enters the
cytoplasm
The next step is Translation!
2.
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RNA ______________
Occurs in the cytoplasm with the aid of a
ribosome.
Each RNA codes for amino acids.
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The RNA is read by reading the codon
sequence.
◦ A codon is 3 BASE PAIRS LONG. Each codon
codes for an amino acid.
 RNA strand: AUGGUUAUUGCG
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For example:
AUGCCCUCAGAG
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RNA strand: AUGGUUAUUGCG
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The appropriate amino acid is placed on the
growing polypeptide chain.
The polypeptide chain then undergoes
structural changes to become a functional
protein!
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If we change the DNA:
◦ RNA will be changed = Protein will be changed
This is what we take advantage of in biotechnology!