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Fatty acids
- Saturated: all carbons are linked by single covalent bonds
- --Tend to be solid at room temperature
- Unsaturated: contain one or more double bonds
- --1 double bond- monounsaturated
- --2 or more – polyunsaturated
- --Tend to be liquids at room temperature (oils)
- Double bonds are easily broken down - not as strong
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Fats are important-
- For energy storage
- --1 gram of fat stores twice as much energy
- --as 1 gram of glycogen or starch
- Fats can also be structural in providing cushioning and insulation
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Phospholipids
- Made up of: glycerol(not a lipid), 2 fatty acids and a phosphate group
- Has a charge
- Amphipathic molecule:
- --Phosphate region- polar, hydrophillic
- --Fatty acid chains- nonpolar, hydrophobic
- Different from other lipids cause it has Phosphorus (P)
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Phospholipid
- Polar head: sometimes will attach to a spot
- - Hydrophilic
- - Has a charge
- - Attached
- Nonpolar tail: Fatty Acids
- - Hydrophobic
- - No charge
- - Unattached
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Steroids
- Four interconnected rings of carbon atoms
- --Usually not very water soluble
- Cholesterol, Estrogen and testosterone differ only slightly
- --Is a lipid
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Proteins/Peptide Bonds
- Composed of carbon, hydrogen, oxygen, nitrogen, and small amounts of other elements, notably sulfur
- --Amino acids are the monomers
- Common structure with variable R-group
- --20 amino acids
- Side-chain determines structure and function
- Peptides: Joined by dehydration or (condensation reaction) - loss of water, makes smaller
- --Peptide bond - amino acids - protein
- --Forms polypeptides
- --Proteins are made up of 1 or more polypeptides
- Broken apart by hydrolysis
- Lirear - popar
- Amino Acids: some are polar some are non polar
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1. Primary structure
- Amino acid sequence
- --Determines what it is
- Determined by genes
- --how the structure comes together
- Linear
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2. Secondary Structure
- Chemical and physical interactions cause folding
- --Folds because if Hydrogen Bonds
- Irregular or repeating
- α helices and β pleated sheets
- --Key determinants of a protein’s characteristics
- “Random coiled regions”
- --Not α helix or β pleated sheet
- --Shape is specific and important to function
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5 factors promoting protein folding and stability
- Hydrogen Bonds: bond between polypeptide backbone and atoms in different side chains
- Ionic Bonds: bonds between oppositely charged side chains
- Hydrophobic Effect: nonpolar amino acids in center of protien to avoid contact with water
- Van der Waals
- Desulfide Bridge: covalent bond form between 2 cysteine side chains
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3. Tertiary structure
- Folding gives complex three-dimensional shape
- Sometimes final level of structure
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4. Quaternary structure
- Made up of 2 or more polypeptides
- --Protein subunits
- --Multimeric proteins
- --Form a functional protein
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Nucleic Acids
- Responsible for the storage, expression, and transmission of genetic information
- Has a negative charge
- --Two classes
- Deoxyribonucleic acid (DNA):Store genetic information coded in the sequence of their monomer building blocks
- Ribonucleic acid (RNA):Involved in decoding this information into instructions for linking together a specific sequence of amino acids to form a polypeptide chain
- DNA:Deoxyribose, AGCT, 2 strands-double helix, 1 form
- --All amino acids put together
- RNA:Ribose, AGCU, single strand, several forms
- --decodes what those different molecules will do
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Monomer
- A nucleotide
- Made up of phosphate group (polar head), a five-carbon sugar (C5-H10-O5) (either ribose or deoxyribose), and a single or double ring of carbon and nitrogen atoms known as a base
- --Sugar-phosphate backbone
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