Biology and Biochemistry Flashcards

Amino Acids

There are 20 of these building blocks of proteins.

Average Amino Acid Weight

Approximately 110 daltons or 0.110 kilodaltons.

Primary Structure of a Protein

Linear sequence of amino acids held together by covalent peptide bonds.

Secondary Structure of a Protein

Local arrangement of amino acids into alpha helices and beta sheets, stabilized by hydrogen bonding.

Tertiary Structure of a Protein

Formation of 3D conformations due to R group interactions such as hydrophobic interactions, Van der Waals forces, hydrophilic interactions, and ionic bonds; disulfide bonds can also form.

Quaternary Structure of a Protein

Multiple subunits coming together to form a single functional unit, stabilized by hydrophobic interactions, hydrogen bonding, or ionic bonding.

Prosthetic Group

A cofactor or coenzyme that is tightly attached to an enzyme and essential for its activity.

Transition state of a reaction

Enzymes bind to this and stabilize it, lowering the reaction's activation energy.

Lyases

Break Bonds.

Isomerases

Rearrange atoms in a molecule.

Ligases

Form bonds; requires energy.

Hydrolases

Performs hydrolysis.

Oxidoreductases

Catalyze redox reactions.

Transferases

Transfers functional groups from one molecule to another.

Effect of Heat on Enzyme-Catalyzed Reaction

Enzyme activity increases up to a point, after which denaturation occurs.

Competitive Inhibitor

Binds at the active site, increases Km, Vmax unchanged.

Non-Competitive Inhibitor

Binds at an allosteric site, Km unchanged, Vmax decreases.

Uncompetitive Inhibitor

Binds to the substrate-enzyme complex, Km decreases, Vmax decreases.

Purines

Two-ring structures, adenine and guanine.

Pyrimidines

Single-ring structures, cytosine, thymine, and uracil.

Phosphates on ATP

Labeled alpha, beta, gamma from left to right.

GC Content

Increases DNA melting point because it has 3 hydrogen bonds.

Carbohydrates

Consist of carbon and water (hydrogen and oxygen).

Simple Carbs

Monosaccharides (glucose, fructose, galactose) and disaccharides (maltose, sucrose, lactose).

Complex Carbs

Polysaccharides (starch, glycogen, cellulose).

Fatty Acid

Has a carboxylic acid group at its end and can attach to a glycerol through esterification.

Triglyceride

Three fatty acids on a glycerol.

Saponification

Triglycerides are hydrolyzed by a strong base and create carboxylic acid salts called soap

Glycerophospholipids

Like triglycerides but have a phosphate and amino alcohol and two fatty acids attached to the glycerol.

Sphingolipids

Have a different backbone; sphingosine. A single fatty acid and a unique functional group like a sugar or phosphate can bind.

ΔG and Keq relations

ΔG=-RTlnKeq.

Glycolysis

Turns glucose into pyruvate (for energy). Occurs in the cytoplasm.

Substrate Level Phosphorylation

Is the transfer of a phosphate group between molecules without the need for energy coupling.

Rate Limiting Step of Glycolysis

The rate limiting step involves phosphofructokinase-1.

Gluconeogenesis

Turns pyruvate to glucose; occurs in the liver.

Primary Active Transport

Uses ATP to move something against its gradient.

Secondary Active Transport

Uses a gradient created by primary active transport to move other molecules by coupling.

Desmosomes

Special cell structures in epithelial tissue that create strong connections between cells to work against mechanical stress; involved in signaling pathways for growth, differentiation, and tissue development.

Gap Junctions

Formed by connexons which are hexamers that make pores where water and solutes are allowed to pass; involved in cell-to-cell communication.

Tight Junctions

Physical link between cells that prevents leakage into the space between cells.

Nucleosome

DNA double helix wraps around histone proteins to make this.

Euchromatin

Less compact, allows for transcription to occur.

Heterochromatin

Densely packed, less availability for transcription.

Functions of polymerase

Repairing DNA, removing primer, replicating DNA.

Wobble

Amino acids have multiple codon combinations that will work for them; the variation in these combination is at the 3rd amino acid of the codon.

Silent Mutation

A change to the DNA sequence that does not result in a change in amino acid sequence.

Hardy-Weinberg Equilibrium

Principle that predicts the distribution of alleles in a population (p + q = 1 and p2+ 2pq + q2).

Bottleneck Effect

Population dramatically reduces in size, leading to lower genetic diversity.

Osteoclast

Breaks down old bone.

Pyruvate Dehydrogenase

Converts pyruvate into acetyl-CoA.

Differentiation

Cell becomes specialized to perform a specific function.

Determination

Assigns fate of cells

Location of Krebs Cycle

Mitochondria matrix.

Location of ETC

Mitochondria IMS.

Location of B-Oxidation

Mitochondria or peroxisomes.

About Gases Dissolving in Liquids

C=kH*P (Henry's Law).

Cross Bridge

Myosin head binds to actin forming this.

Osteoblast

Make new bone.

Chondrocytes

Produces and maintain cartilage.

SDS (Sodium Dodecyl Sulfate)

This gives a uniform negative charge to all proteins involved in SDS PAGE.

Southern Blot

Used to detect specific DNA sequences.

Northern Blot

Used to detect specific RNA sequences.

PCR (Polymerase Chain Reaction)

Amplifies DNA by copying it many times.

Restriction Enzymes

Can cleave DNA at restriction sites which are palindromic DNA sequences.