Chapter 3 Flashcards
Biological molecules consist primarily of
Carbon bonded to carbon or carbon bonded to hydrogen (hydrocarbons)
Functional Groups
Carbon may be bonded to functional groups with specific properties (usually polar)
Hydroxyl
−OH
Carbohydrates, proteins, nucleic acid, lipids
Carbonyl
O
II
−C −
Carbohydrates, nucleic acids
Carboxyl
O
//
−C
\
OH
Proteins, lipids
Amino
H
/
−N
\
H
Proteins, nucleic acids
Sulfhydryl
−S− H
Proteins
Phosphate
O-
|
− O − P− O-
II
O
Nucleic acids
Methyl
H
|
− C− H
|
H
Proteins
Isomers
Molecules with the same chemical formula
Structural isomers
Functional groups attached to different parts of C- skeleton
Bonds in different locations
Stereoisomers
Different arrangements of functional groups on same C- skeleton
Flipped direction
Chiral
Molecules are mirror image
Dextrorotatory- Right hand form
Levorotatory - left hand form
Monomers
Single subunits or “block”
Polymer
Many units or “blocks”
Polypeptide
Protein
Dehydration synthesis
Formation of large molecules by the removal of water (monomers joined to create polymers)
Hydrolysis
Breakdown of large molecules by the addition of water (polymers breakdown to monomers)
Carbohydrates
1:2:1 ratio of carbon, hydrogen, oxygen (CH²O)n
Good energy storage
(C−H breaks bond to create energy)
Monosaccharide
Glucose. Single sugar. 6 carbons. Energy storage
Disaccharides
2 momosaccharides linked together by dehydration synthesis. Used for sugar transport or energy storage
Polysaccharides
Long chains of sugar. Energy storage. Structural support. Plants use starch and cellulose. Animals glycogen (stored in liver). Crustaceans, insects use chitin
Nucleic acids
DNA, RNA, & ATP (energy of cell).
Specialized for storage, transmission, and use of genetic information
Nucleotides
Polymer of nucleic acids.
Sugar+phosphate+nitrogenous base
Deoxyribose
Sugar in DNA
Ribose
Sugar in RNA
Nitrogenous base of purines
Adenine and Guanine
A and G
2 Rings
Nitrogenous base of pyrimidines
Thymine, Cytosine, and Uracil
T, C, and U
Single ring
DNA contains…
A, T, G, and C
RNA contains…
A, U, G, and C
To make a nucleic acid polymers (DNA or RNA)
You need phospodiester bonds (phosphorus connected between nucleotides)
Complementary Purine and Pyrimidines
A&T (2 H bonds)
G&C (3 H bonds)
DNA Helix and function
2 polynucleotide strands connected by Hydrogen bonds. Double Helix
Genetic information carried in sequence of nucleotides
Polynucleotide strands are
complementary
RNA strand type & function
single polynucleotide strand
(Read genetic info on DNA)
Direct the synthesis of proteins
ATP (adenosine triphosphate)
Primary energy use of cells
NAD+ and FAD
carry and move electrons (move energy) for cellular reactions
Protein Functions
Enzyme catalyst
Defense
Transport
Support
Motion
Regulation
Storage
Proteins are …
polymers (polypeptides) of amino acids (monomers)
Amino Acids
20 different (12 synthesized)
joined by dehydration synthesis
Peptide bonds form between adjacent amino acids
Amino Acid structure
Central carbon atom surrounded by
amino group
carboxyl group
single hydrogen
variable R group
R group dictates
Chemical properties of amino acid
Amino Acid classification
Nonpolar
Poplar
charged
aromatic ( ring like)
Special function
Primary structure
sequence of amino acids linked by peptide bonds
Secondary structure
Interaction of groups in the peptide backbone, H-bonds between Amino Acids
(alpha helix, beta sheet)
Tertiary structure
Final folded shape of globular protein with single polypeptide chain.
Quaternary structure
Arrangement of individual chains (subunits) in a protein with 2 or more polypeptide chains
Domains
Specific functions. (Functional units within a larger structure)
Chaperone Proteins
Help proteins fold correctly, form bonds properly and in correct form. Enter chamber and ATP energy alters condition (hydrophilic or hydrophobic)
(Shape determines function)
Denaturation
change in shape of protein, causing loss of function. (Effects secondary, tertiary and quaternary) Not primary
Lipids and main categories
Group of molecules that are insoluble in water (No true monomer)
Fats (triglycerides)
Phospholipids
(Steroids, waxes)
Triglycerides
1 glycerol + 3 fatty acids
Animal fat, plant oil
Store two times more energy than carbohydrates.
Fatty acids (tails/chains) are
Long hydrocarbon chains
saturated
unsaturated
polyunsaturated
Saturated fatty acids
single carbon - carbon bonds
single H - C bonds
(saturated with hydrogen, no double C bonds) Linear, straight, solid at room temp (animal fat, butter)
Unsaturated fatty acids
Some double C bonds. Causes kinks/bends. Liquid at room temp (vegetable oil)
Phospholipids
1 glycerol + 2 fatty acids + 1 phosphate group
Contain polar heads (phosphate, hydrophilic) and nonpolar tails (fatty acid hydrophobic)
Can be saturated or unsaturated
Phospholipids spontaneously form (2 options)
Micelles ( single layer ball) or lipid bilayers.
Micelles
can be formed within cells (ball, single layer) Hydrophobic tail, hydrophilic heads
Phospholipid bilayer
Forms cell membranes, (hydrophobic) tails create selectively permeable barrier for control/regulation. Hydrophilic heads outwards
Carbohydrate cellular structure, polymer, monomer, and type of bond
Starch- chloroplast
Polymer- Starch
Monomer- Monosaccharide
Glycosidic bond (O with 2 sugars)
Nucleic acid cellular structure, polymer, monomer, and type of bond
Chromosome
Monomer - DNA RNA
Polymer- nucleotide
Phosphodiester bonds (phosphate group)
Protein cellular structure, polymer, monomer, and type of bond
Hemoglobin
Monomer - polypeptide
Polymer - amino acid
Peptide bond (O=C - N=H
Lipid cellular structure, polymer, monomer, and type of bond
Phospholipid bilayer
Polymer - triglycerides
Monomer - no true monomer
Ester bonds C - O - C = O
