 Structural = Build the body (skin, hair, muscle, blood)  Enzymes = speed up, slow down, start, or stop cellular/chemical reactions (usually end in –ase)

DNA → Proteins → Traits Controls the _production_ of Controls the _expression_ of How do we get to the “who” we are?

 Trait – a specific characteristic like eye color, or height that varies from one individual to another.  Variation – the _version_ that an organism can inherit of a trait. Traits vs Variations

_Variation_ Of a Trait Differences Within a _Protein_ → Results In

 Trait = Eye color  Variation

 Trait = Hair Color  Variation

 Trait = Skin Color  Variation

 Proteins are made up of repeating units (MONOMERS) called amino acids. All amino acids have a similar basic structure. PROTEINS

 There are only _20_ different amino acids.  A protein may contain anywhere from 50 to 5,000 amino acids. Amino Acids = Protein building blocks

Glucose can be changed back into some amino acids IF certain nitrogen-containing molecules are available. HOWEVER, there are 8 necessary aa that cannot be synthesized in human cells so they have to be ingested in your diet. B/C of this they are called essential amino acids: Isoleucine Leucine Lysine Methionine Phenylalanine Threonine Tryptophan Valine

 A different _number_ and/or _sequence_ of amino acids results in a different protein.

3 parts to an amino acid: 1. Amine Group = -NH 2 2. Carboxyl Group = -COOH 3. R Group = this is the functional group; the part that determines which amino acid you have.

 Amino Acids are linked together by _peptide_ bonds. What determines which protein will be made in the end?

Formation of a Dipeptide Dehydration synthesis

Amino Acid + Amino Acid --> Dipeptide Amino Acid + Dipeptide --> Tripeptide A.A. + A.A. + …..+ Tripeptide --> Polypeptide/Protein

WHAT VARIATION of TRAITS DO YOU HAVE?

EYE COLOR

HAIR COLOR/TEXTURE

FEMALE OR MALE?

WIDOW’S PEAK Dominant

TONGUE ROLLING Homozygous recessives- non rollers

FRECKLES

DIMPLES/CLEFT CHIN Dominant Images from:

Bend finger at top joint?

HITCHHIKER’S THUMB =homozygous recessive Images from:

LONG 2 nd TOE Dominant

ATTACHED EAR LOBES homozygous recessive = attached

Touch your nose with your tongue? Images from:

COLOR BLINDNESS RED-green colorblindness most common 8% of males & 0.5% females

 What controls the production of proteins?  What determines which protein is made?  What controls the expression of traits?