DNA
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DNA is a double-stranded double helix (twisted ladder)
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A base pair creates one rung of the ladder
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The sequence of bases (ATCG) determines instructions for life
4 Nitrogen Bases:
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A – Adenine
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T – Thymine
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C – Cytosine
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G – Guanine
Adenine always pairs with thymine
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2 hydrogen bonds between them
Cytosine always pairs with guanine
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3 hydrogen bonds between them
DNA backbone is made of:

P – Phosphate

S – Sugar (deoxyribose)
RNA


RNA is single-stranded DNA
Used for making protein
4 Nitrogen Bases:

A – Adenine

U – Uracil (Replaced Thymine in DNA)

C – Cytosine

G – Guanine
Adenine always pairs with uracil

2 hydrogen bonds between them
Cytosine always pairs with guanine

3 hydrogen bonds between them
RNA backbone is made of:

P – Phosphate

S – Sugar (ribose)

DNA Replication:
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Purpose: to make an exact copy of DNA for cell division
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Process: o DNA Gyrase unwinds the DNA o DNA Helicase unzips the DNA o Free bases attach to the DNA
RNA Transcription:
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Purpose: To make protein
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Process: o DNA Gyrase unwinds the DNA o RNA Polymerase unzips the DNA o Free RNA bases attach to one side of the DNA
RNA Translation:
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Purpose: To make protein
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Process: o Every three bases creates one amino acid o Amino acids connect to make a protein
Gene: section of DNA that codes for a trait (hair color, eye color, etc.)
Mutations:
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Substitution o Base pair is substituted for another
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Deletion o Base pair is deleted
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Addition o Base pair is added
Mutations can:
1. Can help you.
2. Can harm you.
3. Have no effect on you.
Restriction Enzyme:
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Enzyme that cuts DNA at a specific sequence
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Example: o TATA o CCCGG