List: Four Main Classes of Large Biological Molecules
a. carbohydrates
b. lipids
c. proteins
d. nucleic acids
Define: Macromolecule
giant molecules
Define: Polymer
a. long molecule consisting of many similar or identical building blocks linked by covalent bonds
b. carbohydrates, proteins, and nucleic acids
Define: Monomer
small molecules that are the repeating units that serve as the building blocks of a polymer
Define: Condensation Reaction
a reaction in which two molecules are covalently bonded to each other through loss of a molecule
Define: Dehydration Reaction
a. a specific condensation reaction in which the molecule lost is water
b. monomers are connected by these reactions
Define: Hydrolysis
a. the addition of water molecules breaks bonds, the opposite of dehydration
b. polymers are disassembled to monomers by this process
Describe: Hydrolysis and Digestion
most food is made of polymers, so in the digestive tract, enzymes speed up hydrolysis, breaking the food into monomers; the monomers can then be used to make polymers different from the ones that were digested
Define: Carbohydrates
a. sugars and polymers of sugars
b. macromolecules are polysaccharides
Describe: Monosaccharides
a. simplest carbohydrates, also called simple sugars
b. molecular formulas are some multiple of the unit CH20
c. most common is glucose (C6H12O6)
Describe: Sugars
a. the molecules have a carbonyl group and multiple hydroxyl groups
b. depending on the location of the carbonyl group, the sugar is either an aldose (end) or ketose (middle)
c. size of carbon skeleton ranges from 3 to 7 carbons long
d. function depends o
Describe: Disaccharides
double sugars, consisting of two monosaccharides joined by a glycosidic linkage
Define: Glycosidic Linkage
a covalent bond formed between two monosaccharides by a dehydration reaction
Describe: Sucrose
most common disaccharide; two monomers are glucose and fructose (structural isomers)
Define: Polysaccharide
macromolecules, polymers with a few hundred to thousand monosaccharides joined by glycosidic linkages
Define: Starch
a. storage polysaccharide in plants
b. polymer of all alpha glucose monomers
c. joined by mostly 1-4 glycosidic linkages, making the polymer helical
Describe: Types of Starch
a. simplest form is amylose, which is unbranched since it is all 1-4 linkages
b. more complex form is amylopectin, branched polymer with 1-6 linkages at branch points
Define: Glycogen
a. a polymer of glucose that is like amylopectin, but more extensively branched
b. animal storage polysaccharide mainly in the liver and muscles
Define: Cellulose
a. structural polysaccharide, a polymer of beta glucose
b. major component of the tough cell walls
c. most abundant organic compound on earth
d. human enzymes cannot digest cellulose because of the beta configuration of glucose
Describe: Microfibrils
units of parallels cellulose molecules in plant cell walls
Define: Chitin
structural polysaccharide used by arthropods to build their exoskeletons; similar to cellulose, but the glucose monomer has a nitrogen containing appendage
Define: Lipids
a. smaller than true macromolecules and not polymers
b. contain mostly hydrocarbons
c. hydrophobic
d. include waxes, pigments, etc.
List: Most Important Lipids
a. fats
b. phospholipids
c. steroids
Describe: Fats
a. not polymers
b. constructed from glycerols and fatty acids, usually three fatty acid molecules joined to the glycerol by an ester linkage
c. major function is energy storage
Describe: Ester Linkage
bond between a hydroxyl group and a carboxyl group
Describe: Glycerol and Fatty Acids
a. gylcerol is an alcohol with three carbons, each with a hydroxyl group
b. a fatty acid has a carbon skeleton with a carboxyl at one end
Define: Triacylglycerol
three fatty acids linked to one glycerol molecule, a basic fat
Define: Saturated Fatty Acid
a. when there are no double bonds in the hydrocarbon chains
b. make up saturated fats, which are unhealthy
Define: Unsaturated Fatty Acid
when the fatty acids have one or more double bonds
Describe: Adipose Cells
where humans and other mammals stock their long term food reserves (fat)
Define: Phospholipid
a. two fatty acids attached to a glycerol
b. a hydroxyl group of the glycerol is attached to a phosphate group with a negative charge
Describe: Phospholipid Bilayers
form bilayers in water so that hydrophilic heads (phosphate group) are on the outside facing the water, and hydrophobic tails (fatty acids) are on the inside
Define: Steroids
lipids characterized by a carbon skeleton consisting of four fused rings
Define: Cholesterol
a. a steroid in animal cell membranes
b. a precursor from which other steroids are synthesized
Define: Enzymes
a. most important proteins
b. regulate metabolism by acting as catalysts, chemical agents that selectively speed up chemical reactions without being consumed in the reaction
Define: Polypeptides
a. polymers of amino acids
b. constructed from the same set of 20 amino acids
c. formed by peptide bonds
d. at one end is a free amino group, and at the other end is a free carboxyl group
Define: Protein
consists of one or more polypeptides folded and coiled into specific conformations
Define: Amino Acids
a. organic molecules possessing both carboxyl and amino groups
b. center of the amino acid is an asymmetric carbon called the alpha carbon; its four different partners are the amino group, carboxyl group, a hydrogen atom, and an R group
Describe: R Group in Amino Acids
a variable group in the amino acid, also called the side chain
Describe: Acidic and Basic Amino Acids
a. acidic amino acids usually have negatively charged side chains, because of a carboxyl group
b. basic amino acids usually have positively charged side chains
c. both are hydrophilic
Define: Peptide Bond
a dehydration between two amino acids that are positioned so that the carboxyl group of one is adjacent to the amino group of another
Describe: Levels of Protein Structure
a. primary structure is a string of amino acids
b. secondary structure is the amino acids in either a coil or pleats, as a result of hydrogen bonds
c. tertiary structure is the coils or pleats forming a shape due interactions between the R groups
d. quate
Describe: Key Factors in Protein Conformation
a. interactions responsible for secondary and tertiary structure
b. physical and chemical conditions of the environment (pH, salt, concentration, temperature, etc.)
Define: Denaturation
a. when a protein unravels and loses its native conformation
b. most proteins become denatured when transferred from an aqueous environment to an organic solvent
Define: Chaperonins
protein molecules that assist the proper folding of other proteins; work by keeping the new polypeptide separate from "bad influences
Define: X-Ray Crystallography
important method used to determine a protein's three-dimensional structure
Define: Gene
a unit of inheritance that consist of DNA
Describe: DNA
a polymer belonging to the class of nucleic acids
List: Types of Nucleic Acids
a. deoxyribonucleic acid (DNA); double helix of two polynucleotides
b. ribonucleic acid (RNA); single polynucleotide chain
Describe: Functions of DNA and RNA
DNA directs RNA synthesis, and RNA directs protein synthesis
Describe: Ribosomes
the sites of protein synthesis, in the cell cytoplasm
Define: Polynucleotides
a. macromolecules of polymers of nucleic acids
b. consist of monomers of nucleotides
Define: Nucleotide
a. composed of three parts: nitrogenous base, pentose (5 carbon sugars), and phosphate group attached to the 5' carbon of the sugar
List: Nitrogenous Bases
a. pyrimidines (6 membered ring of carbon and nitrogen): cytosine, thymine, uracil
b. purines (6 membered ring fused to a 5 membered ring): adenine, guanine
Describe: Phosphodiester Linkages
covalent bonds between the -OH of the 3' carbon of one nucleotide and the phosphate on the 5' carbon of the next; hold together adjacent nucleotides
Describe: DNA Double Helix
a. two polynucleotide strands spiral around each other forming a double helix
b. the polynucleotides are held together by phosphodiester linkages
c. the two strands are held together in the middle by hydrogen bonds between the paired bases, and van der Wa
Define: Antiparallel
the two sugar-phosphate backbones of DNA run in opposite 5' to 3' directions from each other
List: Four Main Classes of Large Biological Molecules
a. carbohydrates
b. lipids
c. proteins
d. nucleic acids
Define: Macromolecule
giant molecules
Define: Polymer
a. long molecule consisting of many similar or identical building blocks linked by covalent bonds
b. carbohydrates, proteins, and nucleic acids
Define: Monomer
small molecules that are the repeating units that serve as the building blocks of a polymer
Define: Condensation Reaction
a reaction in which two molecules are covalently bonded to each other through loss of a molecule
Define: Dehydration Reaction
a. a specific condensation reaction in which the molecule lost is water
b. monomers are connected by these reactions
Define: Hydrolysis
a. the addition of water molecules breaks bonds, the opposite of dehydration
b. polymers are disassembled to monomers by this process
Describe: Hydrolysis and Digestion
most food is made of polymers, so in the digestive tract, enzymes speed up hydrolysis, breaking the food into monomers; the monomers can then be used to make polymers different from the ones that were digested
Define: Carbohydrates
a. sugars and polymers of sugars
b. macromolecules are polysaccharides
Describe: Monosaccharides
a. simplest carbohydrates, also called simple sugars
b. molecular formulas are some multiple of the unit CH20
c. most common is glucose (C6H12O6)
Describe: Sugars
a. the molecules have a carbonyl group and multiple hydroxyl groups
b. depending on the location of the carbonyl group, the sugar is either an aldose (end) or ketose (middle)
c. size of carbon skeleton ranges from 3 to 7 carbons long
d. function depends o
Describe: Disaccharides
double sugars, consisting of two monosaccharides joined by a glycosidic linkage
Define: Glycosidic Linkage
a covalent bond formed between two monosaccharides by a dehydration reaction
Describe: Sucrose
most common disaccharide; two monomers are glucose and fructose (structural isomers)
Define: Polysaccharide
macromolecules, polymers with a few hundred to thousand monosaccharides joined by glycosidic linkages
Define: Starch
a. storage polysaccharide in plants
b. polymer of all alpha glucose monomers
c. joined by mostly 1-4 glycosidic linkages, making the polymer helical
Describe: Types of Starch
a. simplest form is amylose, which is unbranched since it is all 1-4 linkages
b. more complex form is amylopectin, branched polymer with 1-6 linkages at branch points
Define: Glycogen
a. a polymer of glucose that is like amylopectin, but more extensively branched
b. animal storage polysaccharide mainly in the liver and muscles
Define: Cellulose
a. structural polysaccharide, a polymer of beta glucose
b. major component of the tough cell walls
c. most abundant organic compound on earth
d. human enzymes cannot digest cellulose because of the beta configuration of glucose
Describe: Microfibrils
units of parallels cellulose molecules in plant cell walls
Define: Chitin
structural polysaccharide used by arthropods to build their exoskeletons; similar to cellulose, but the glucose monomer has a nitrogen containing appendage
Define: Lipids
a. smaller than true macromolecules and not polymers
b. contain mostly hydrocarbons
c. hydrophobic
d. include waxes, pigments, etc.
List: Most Important Lipids
a. fats
b. phospholipids
c. steroids
Describe: Fats
a. not polymers
b. constructed from glycerols and fatty acids, usually three fatty acid molecules joined to the glycerol by an ester linkage
c. major function is energy storage
Describe: Ester Linkage
bond between a hydroxyl group and a carboxyl group
Describe: Glycerol and Fatty Acids
a. gylcerol is an alcohol with three carbons, each with a hydroxyl group
b. a fatty acid has a carbon skeleton with a carboxyl at one end
Define: Triacylglycerol
three fatty acids linked to one glycerol molecule, a basic fat
Define: Saturated Fatty Acid
a. when there are no double bonds in the hydrocarbon chains
b. make up saturated fats, which are unhealthy
Define: Unsaturated Fatty Acid
when the fatty acids have one or more double bonds
Describe: Adipose Cells
where humans and other mammals stock their long term food reserves (fat)
Define: Phospholipid
a. two fatty acids attached to a glycerol
b. a hydroxyl group of the glycerol is attached to a phosphate group with a negative charge
Describe: Phospholipid Bilayers
form bilayers in water so that hydrophilic heads (phosphate group) are on the outside facing the water, and hydrophobic tails (fatty acids) are on the inside
Define: Steroids
lipids characterized by a carbon skeleton consisting of four fused rings
Define: Cholesterol
a. a steroid in animal cell membranes
b. a precursor from which other steroids are synthesized
Define: Enzymes
a. most important proteins
b. regulate metabolism by acting as catalysts, chemical agents that selectively speed up chemical reactions without being consumed in the reaction
Define: Polypeptides
a. polymers of amino acids
b. constructed from the same set of 20 amino acids
c. formed by peptide bonds
d. at one end is a free amino group, and at the other end is a free carboxyl group
Define: Protein
consists of one or more polypeptides folded and coiled into specific conformations
Define: Amino Acids
a. organic molecules possessing both carboxyl and amino groups
b. center of the amino acid is an asymmetric carbon called the alpha carbon; its four different partners are the amino group, carboxyl group, a hydrogen atom, and an R group
Describe: R Group in Amino Acids
a variable group in the amino acid, also called the side chain
Describe: Acidic and Basic Amino Acids
a. acidic amino acids usually have negatively charged side chains, because of a carboxyl group
b. basic amino acids usually have positively charged side chains
c. both are hydrophilic
Define: Peptide Bond
a dehydration between two amino acids that are positioned so that the carboxyl group of one is adjacent to the amino group of another
Describe: Levels of Protein Structure
a. primary structure is a string of amino acids
b. secondary structure is the amino acids in either a coil or pleats, as a result of hydrogen bonds
c. tertiary structure is the coils or pleats forming a shape due interactions between the R groups
d. quate
Describe: Key Factors in Protein Conformation
a. interactions responsible for secondary and tertiary structure
b. physical and chemical conditions of the environment (pH, salt, concentration, temperature, etc.)
Define: Denaturation
a. when a protein unravels and loses its native conformation
b. most proteins become denatured when transferred from an aqueous environment to an organic solvent
Define: Chaperonins
protein molecules that assist the proper folding of other proteins; work by keeping the new polypeptide separate from "bad influences
Define: X-Ray Crystallography
important method used to determine a protein's three-dimensional structure
Define: Gene
a unit of inheritance that consist of DNA
Describe: DNA
a polymer belonging to the class of nucleic acids
List: Types of Nucleic Acids
a. deoxyribonucleic acid (DNA); double helix of two polynucleotides
b. ribonucleic acid (RNA); single polynucleotide chain
Describe: Functions of DNA and RNA
DNA directs RNA synthesis, and RNA directs protein synthesis
Describe: Ribosomes
the sites of protein synthesis, in the cell cytoplasm
Define: Polynucleotides
a. macromolecules of polymers of nucleic acids
b. consist of monomers of nucleotides
Define: Nucleotide
a. composed of three parts: nitrogenous base, pentose (5 carbon sugars), and phosphate group attached to the 5' carbon of the sugar
List: Nitrogenous Bases
a. pyrimidines (6 membered ring of carbon and nitrogen): cytosine, thymine, uracil
b. purines (6 membered ring fused to a 5 membered ring): adenine, guanine
Describe: Phosphodiester Linkages
covalent bonds between the -OH of the 3' carbon of one nucleotide and the phosphate on the 5' carbon of the next; hold together adjacent nucleotides
Describe: DNA Double Helix
a. two polynucleotide strands spiral around each other forming a double helix
b. the polynucleotides are held together by phosphodiester linkages
c. the two strands are held together in the middle by hydrogen bonds between the paired bases, and van der Wa
Define: Antiparallel
the two sugar-phosphate backbones of DNA run in opposite 5' to 3' directions from each other