Chapter 5 Flashcards
What are the four classes of large biological molecules?
Carbohydrates, Lipids, Proteins, and Nucleic Acids
What is a polymer?
A polymer is a long molecule consisting of many similar building blocks
What are monomers?
The repeating units that serve as building blocks
Which 3 of the 4 molecules are polymers?
Carbohydrates, Proteins, Nucleic Acids
What are carbohydrates made of?
Carbon, Hydrogen, and Oxygen
What are lipids made of?
Carbon, Hydrogen, less Oxygen
What are proteins made of?
Carbon, Hydrogen, Oxygen, Nitrogen
What are amino acids made of?
Carbon, Hydrogen, Oxygen, Sulfur
What are nucleic acids made of?
Carbon, Hydrogen, Oxygen, Phosphates
What are enzymes?
Enzymes are specialized macromolecules that speed up chemical reactions such as those that make or break down polymers
When does a dehydration reaction occur?
A dehydration reaction occurs when two monomers bond together through the loss of a water molecule, removes a water molecule to form a new bond
How are polymers disassembled to monomers?
through hydrolysis, a reaction that is essentially the reverse of the dehydration reaction (breaks apart polymers), adding a water molecule that breaks a bond
What are carbohydrates?
Carbohydrates include sugars and the polymers of sugars (polysaccharides), simplest sugars are monosachharides
What is a disaccharide?
A disaccharide is formed when a dehydration reaction joins two monosaccharides, this is called a glycosidic linkage
What is starch?
starch is a storage polysaccharide of plants, that consists entirely of glucose monomers, the simplest form of starch is amylose (surplus starch is stored within chloroplasts and other plastids)
What are the two types of starch?
Amylose (unbranched), Amylopectin (somewhat branched)
What is glycogen?
Glycogen is a storage polysaccharide in animals and is stored mainly in liver and muscle cells, hydrolysis of glycogen in these cells releases glucose when there is a demand for sugar
Is glycogen branched or unbranched?
Branched
What is cellulose?
the polysaccharide cellulose is a major component of the tough wall of plant cells, cellulose is a polymer of glucose, it is unbranched
How does cellulose breakdown?
Cellulose in food passes through as an “insoluble fiber”, some microbes use enzymes to digest cellulose, enzymes that digest start cant hydrolyze beta linkages in cellulose
What is chitin?
Chitin is another structural polysaccharide that is found in the exoskeleton of arthropods, provides structural support for cell walls of fungi, is embedded in proteins
What are lipids?
Lipids do not include true polymers, they mix poorly with water and are hydrophobic, consist of hydrocarbons that form nonpolar covalent bonds and are hydrophobic
what are fats constructed from
fats are constructed from two types of smaller molecules: glycerol and fatty acids , they are triglycerides
what are saturated fatty acids
have the maximum number of hydrogen atoms possible and no double bonds, most animal fats
what are unsaturated fatty acids
have one or more double bonds, most plant and fish fats
how do saturated fatty acids behave at room temp compared to unsaturated
saturated: solid, unsaturated: liquid
what is hydrogenation?
the process of converting unsaturated fats to saturated fats by adding hydrogen
what is the major function of fats?
energy storage, cushion vital organs, insulate the body, store long-term food reserves
what is a phospholipid?
two fatty acids and a phosphate that are attached to a glycerol
which parts of a phospholipid are hydrophobic?
the phosphate head is hydrophilic, the fatty acid tails are hydrophobic
what are steroids?
steroids are lipids characterized by a carbon skeleton consisting of four fused rings
what is cholesterol?
a type of steroid that is a component in animal cell membranes
What are proteins constructed of?
Amino acids, polypeptides are unbranched polymers built from these amino acids, a protein consists of one or more polypeptides
what are amino acids?
amino acids are organic molecules with amino and carboxyl groups, differing side chains due to differing R groups
What is the polymer of amino acids?
polypeptides, amino acids are linked by covalent bonds called peptide bonds
what does a functional protein consist of?
one or more polypeptides precisely twisted, folded, coiled, into a unique shape
what is the primary structure of a protein?
its unique sequence of amino acids, determined by genetic information
what is the secondary structure of a protein?
consists of coils and folds in the polypeptide chain
what is the tertiary structure of a protein?
determined by interactions among the various side chains (R groups), the overall shape of the polypeptide
Quaternary structure results when?
a protein consists of multiple polypeptide chains to form a macromolecule
what are the typical secondary structures?
a coil called an alpha helix and a folded structure called a beta pleated sheet
what is hemoglobin?
a globular protein consisting of four polypeptides, two alpha and two beta chains
what can cause a protein to denature?
alterations in pH, salt concentration, temperature
define denaturation
the loss of a protein’s native structure, becomes biologically inactive
what are chaperonins?
chaperonins are protein molecules that assist the proper folding of other proteins
What is the amino acid sequence of a polypeptide programmed by?
a gene, they consist of DNA: a nucleic acid made of monomers called nucleotides
what are nucleic acids made of, their monomer
monomers called nucleotides
what are the two types of nucleic acids?
deoxyribonucleic and ribonucleic,
what is gene expression?
the process of DNA directing synthesis of messenger RNA (mRNA) and through it, controls protein synthesis
What does each nucleotide consist of?
a nitrogenous base, a pentose sugar, and one or more phosphate groups (portion without phosphate group is nucleoside)
What are the two families of nitrogenous bases?
Pyrimidines (cytosine, thymine, uracil): has 1 ring (6 members)
Purines (adenine, guanine): has 2 rings (6 membered & 5 membered)
In DNA the sugar is … In RNA the sugar is….
deoxyribose, ribose
what is a nucleotide made of??
a nucleoside and a phosphate group
what does deoxyribose mean?
without oxygen
base pairing rules for DNA
A and T, G and C
base pairing rules for RNA
A and U, G and C
base pairing rules for RNA
A and U, G and C
how many hydrogen bonds are between a and t
2
how many hydrogen bonds are between g and c
3
