Acids, Bases, Biomolecules, and Protein Structure

Flashcards covering key terms and concepts related to acids, bases, pH scale, buffers, homeostasis, biomolecules, and protein/amino acid structure.

Proton ($H^+$)

A positively charged hydrogen ion whose concentration $[H^+]$ in a solution determines its pH.

Hydroxide ion ($OH^-$)

A negatively charged ion released during the dissociation of water molecules ($H_2O \rightleftharpoons H^+ + OH^-$).

Acid

A substance with a pH below 7 that gives up protons easily and releases excess $H^+$ into a solution.

Base

A substance with a pH above 7 that accepts $H^+$, releases $OH^-$ ions, and reduces the concentration of $H^+$ in a solution.

pH Formula

The inverse logarithmic equation $pH = -\text{log}[H^+]$ on a scale from 0 to 14, where higher $[H^+]$ yields a lower pH value.

Buffer

A chemical that can absorb or release $H^+$ to maintain a constant pH in a solution.

Homeostasis

The process of maintaining a constant internal environment within living cells.

Respiratory alkalosis

A condition in which blood pH becomes more basic due to loss of $CO_2$ during heavy respiration or hyperventilation.

Salicylic Acid

An acidic chemical ($C_9H_8O_4$) that releases excess $H^+$ ions, causing blood pH to remain acidic even during hyperventilation.

Organic Chemistry

The scientific study of carbon-containing molecules.

Monomer

A single basic building block that can bond with other identical or similar molecules to form a polymer.

Polymer

A large molecule composed of repeating monomer units linked together by covalent bonds.

Dehydration synthesis

A chemical reaction that joins monomers together to build polymers, releasing a water molecule ($H_2O$) in the process.

Hydrolysis

A chemical reaction that breaks polymers down into individual monomers through the addition of a water molecule ($H_2O$).

Amino acid

The monomer building block of proteins, consisting of a central carbon atom bound to an amino group ($-NH_2$), a carboxyl group ($-COOH$), an $H$ atom, and a variable R-group.

R-group

The variable side chain of an amino acid that determines its unique chemical properties, categorized as non-polar, polar, or charged.

Peptide bond

The covalent chemical bond formed via a dehydration reaction that connects amino acids into a polypeptide chain.

N-terminus

The end of a polypeptide chain featuring a free amino group.

C-terminus

The end of a polypeptide chain featuring a free carboxyl group.