Biochemistry and Cell Signaling Lecture Flashcards

Flashcards covering core biochemistry and cell signaling topics including hydrogen bonding, protein primary and tertiary structure, DNA base properties, and membrane receptors.

Hydrogen Bond Donor

A compound containing a hydrogen atom covalently bound to a highly electronegative atom (like nitrogen) with a partial positive charge, capable of forming a bond with a lone electron pair of O, N, S, or F (represented by compound D in the diagram).

Hydrogen Bond Acceptor

An electronegative atom (such as N, F, or O) containing unshared lone electron pairs capable of accepting a hydrogen bond.

Peptide Sequence Ile-Leu-Val-Trp-Ser-Arg-Lys-Cys-Arg-Ser

A ten-amino-acid peptide sequence (I-L-V-W-S-R-K-C-R-S) featuring a nonpolar N-terminal domain (ILVW) and a hydrophilic C-terminal domain.

ILVW Amino Acid Cluster

A nonpolar (apolar) amino acid segment consisting of Isoleucine, Leucine, Valine, and Tryptophan that favorable interacts with nonpolar solvents like oil and folds inward in water.

Melanocortin Receptor 1 (MR-1)

A cell membrane receptor composed of 7 transmembrane helical domains traversing the lipid bilayer, requiring hydrophobic amino acid residues in its membrane-spanning segments.

Ovalbumin Denaturation

The structural unfolding and visual change of egg white protein upon heating, caused by the breakdown of non-covalent higher-order protein interactions.

Chargaff's Equalities in DNA

Mathematical relationships in double-stranded DNA where $A + G = C + T$, $G/C = 1$, and $A/T = C/G$ due to specific base-pairing rules.

Branched Storage Polysaccharides

Polymeric carbohydrate storage molecules like animal glycogen and plant starch, whose highly branched architecture facilitates efficient energy packaging and rapid enzymatic cleavage.

Phospholipids in Nonpolar Solvents

An inverted micellar or membrane organization where hydrophilic head groups aggregate inward away from oil while hydrophobic fatty acid tails extend outward into the nonpolar environment.

Siberian Anthrax Spores

Dormant bacterial spore structures capable of remaining viable and infectious over centuries under harsh environmental conditions.

Cyclic AMP (cAMP)

A key intracellular second messenger molecule used across diverse signaling pathways to relay extracellular signals internally.

Quorum Sensing

An intercellular communication process used by bacteria to monitor population density and coordinate group behavior.

Protein Phosphorylation

A reversible regulatory mechanism in signal transduction where phosphate groups are added to target proteins to alter their biological activity.

Emergence

The biological concept wherein novel properties and complex capabilities arise at higher levels of structural organization that cannot be explained solely by examining individual underlying molecular components.

Linear Peptide Structure Analysis

Determination of a peptide's solubility and environmental fitness based on the sequence of its constituent polar and nonpolar amino acid residues.