Biochemistry Review Flashcards

Flashcards to review key concepts in biochemistry, covering biomolecules, lipids, carbohydrates, proteins, enzymes, energy generation, and nucleic acids.

What MUST be part of a functional group in a molecule?

Any atom other than carbon or hydrogen.

What are the functions of proteins?

Structure, enzymes, storage, signaling.

What are the functions of carbohydrates?

Structure, energy storage.

What are the functions of lipids?

Energy storage, cell membranes, signals.

What are the functions of nucleic acids?

Information storage, information transfer, regulation.

What is the result of hydrogenation of unsaturated fatty acids?

Convert vegetable oils into solid fats; can produce trans fats.

What are carbohydrates chemically defined as?

Polyhydroxy aldehydes and ketones.

What is a monosaccharide?

An individual sugar.

What is a disaccharide?

Two sugars bonded together.

What is a polysaccharide?

Many sugars linked together.

What is a glycosidic bond?

A bond between two sugars.

What are chiral carbons?

Carbon atoms with four different groups bonded to them.

What are enantiomers?

Stereoisomers that are mirror images of each other.

What are diastereomers?

Stereoisomers that are not mirror images.

What is a racemic mixture?

A mixture where both enantiomers are present.

What is polarimetry?

Method using polarized light to distinguish between enantiomers.

What does the alcohol group on the chiral carbon farthest from the carbonyl group determine?

The determination of D or L structure.

What is the anomeric carbon?

The carbon of the aldehyde or ketone in a ring structure.

What is lactose?

A disaccharide of galactose and glucose; milk sugar.

What is fructose?

A ketohexose; fruit sugar or levulose.

What is glucose?

An aldohexose; dextrose or blood sugar.

What is cellulose?

A polymer of glucose; the most common organic molecule in the world, found in plants.

What is chitin?

A modified sugar polymer that makes up the exoskeleton of arachnids, lobsters, crabs, and scorpions.

What is the difference between glycogen and starch?

Plants store glucose as while animals store glucose as

What is a peptide bond?

Bond formed by bonding amino acids together.

What is bonded to the alpha carbon in an amino acid?

Amine, carboxylic acid, hydrogen, and a side chain (R group)

What is the primary structure of a protein?

Sequence of amino acids in the protein chain (N-terminus to C-terminus).

What is the secondary structure of a protein?

Alpha helices and beta sheets formed by hydrogen bonding between backbone atoms.

What is the tertiary structure of a protein?

Overall folding and bending of a single peptide chain.

What is the quaternary structure of a protein?

Interactions between multiple peptide chains.

What is denaturation of a protein?

Interruption of secondary through quaternary structures.

Name six agents that can cause denaturation of proteins.

Heat, change in pH, detergents, inorganic salts, mechanical agitation, and organic solvents

What are prions?

Disease agents that are incorrectly folded proteins, that can cause native proteins to misfold.

What are enzymes?

Biological catalysts that speed up reactions without being used up.

What is the active site of an enzyme?

Place on the enzyme where the chemical reaction occurs.

What are allosteric sites?

Regions where small molecules bind and alter the enzyme's ability to function.

What is a cofactor?

A non-protein component necessary for enzyme activity (e.g., metal ion, heme group, organic molecule).

What are the six categories of enzymes?

Oxidoreductases, transferases, hydrolases, isomerases, lyases, and ligases

What is a zymogen?

A precursor protein that needs to be activated.

What are competitive inhibitors?

Inhibitors that bind the enzyme in the active site, but do not undergo a reaction

What are suicide inhibitors?

Inhibitors that react with and alter the enzyme, permanently disabling it.

Give at least one example of enzymes used to monitor tissue health

AST and ALT

What is metabolism?

The sum of all processes that happen in a cell.

What is anabolism?

Buildup of molecules, usually requiring energy input.

What is catabolism?

Breakdown of molecules, usually creating energy.

What is digestion?

Conversion of bulk food into small molecules that can be absorbed.

What is stage two of energy generation?

Conversion of small molecules (glucose, fatty acids, amino acids) into acetyl-CoA.

What is stage three of energy generation?

Citric acid cycle, tricarboxylic acid cycle, or Krebs cycle.

What is stage four of energy generation?

Electron transport chain (ETC) and oxidative phosphorylation.

What is the lack of insulin known as in diabetes?

Diabetes type I

What is insulin resistance known as in diabetes?

Diabetes type II

What are reactive oxygen species?

Superoxide ion, hydrogen peroxide, and hydroxyl radical.

What enzymes and vitamins are antioxidants used to fight reactive oxygen species?

Superoxide dismutase, catalase, and vitamins E, C, and A.

What occurs in the body when GLucose is temporarily stored as glycogen?

Glycogenesis

What occurs when Glycogen is released?

Glycogenolysis

What does 'essential' mean in terms of nutritional needs?

They cannot be produced by our cells and must be in our diets.

What are glucogenic amino acids?

Those that are converted into pyruvate or a Krebs cycle intermediate and can feed into gluconeogenesis.

What transports triglycerides and cholesterol in the blood?

Lipoproteins

What are the four major lipoproteins?

Chylomicrons -> VLDL -> IDL -> LDL -> HDL

What is known as 'bad cholesterol'?

LDL

What is known as 'good cholesterol'?

HDL

What are the starting and ending metabolites in Glycolysis?

Glucose -> Pyruvate (ATP, NADH)

What are the starting and ending metabolites in Aerobic?

Pyruvate -> Acetyl-CoA (NADH)

What are the starting and ending metabolites in Anaerobic?

Pyruvate -> Lactic acid (humans) / Ethanol (yeast)

What are the starting and ending metabolites in Gluconeogenesis?

Pyruvate -> Glucose

What are the starting and ending metabolites in Glycogenesis?

Glucose-6-P -> Glycogen

What are the starting and ending metabolites in Glycogenolysis?

Glycogen -> Glucose-6-P

What are the starting and ending metabolites in Krebs Cycle (TCA, CAC)?

Acetyl-CoA -> CO2 (ATP, NADH, FADH2)

What are the starting and ending metabolites in the Electron Transport Chain?

NADH, FADH2 -> Hydrogen ion gradient/O2 -> 2 H2O

What are the starting and ending metabolites in Oxidative Phosphorylation?

ADP, Pi -> ATP

What are the starting and ending metabolites in Fatty Acid Oxidation?

Fatty acids -> Acetyl-CoA (NADH, FADH2)

What are the starting and ending metabolites in Lipogenesis?

Acetyl-CoA -> Fatty acids

What are the starting and ending metabolites in Ketogenesis?

Acetyl-CoA -> Ketone bodies

What are the starting and ending metabolites in the Urea Cycle?

NH3, CO2 -> Urea

What is the Central Dogma of Molecular Biology?

DNA -> RNA -> Protein

What are the bases found in nucleotides?

Adenine, guanine, thymine (DNA only), cytosine, uracil (RNA only).

What are the key structural differences between DNA and RNA?

DNA contains deoxyribose; RNA contains ribose. DNA has thymine; RNA has uracil. DNA is double-stranded; RNA is single-stranded.

What are the different types of RNA?

hnRNA -> mRNA -> tRNA -> rRNA

Describe the process of DNA replication.

Leading strand is copied continuously; lagging strand is copied in sections (Okazaki fragments). New copies each contain a new strand and an old strand in a semiconservative fashion

Explain the role of DNA and RNA in heredity and genetic expression.

DNA is the information carrier and children inherit DNA from both parents.