BIO 1400/1401: Biomolecules and Cells

Flashcards about Biomolecules and Cells Lecture Topics

Atoms

Building blocks of all matter in the Universe

Electrons

Negatively charged particles found in orbitals within shells

Protons

Positively charged particles found in the nucleus

Neutrons

Neutral particles found in the nucleus

Atomic Number

Number of protons in an atom

Atomic Mass Number

Sum of the number of protons and neutrons in an atom

Orbital

Physical region or space where an electron is expected to be present

Ground State

Lowest energy level of an orbital

s orbital

Orbital with the lowest energy

Shells

Orbitals arranged in form of shells; innermost shell has one orbital (1s)

Hund's Rule

Each electron will first fill all the orbitals with similar energy before pairing with another electron in a half-filled orbital

Chemical Bond

Attraction between atoms that results into the formation of a chemical compound

Covalent Bond

Results from the equal sharing of electrons between two atoms

Single Covalent Bond

Represents the sharing of two valence electrons

Noncovalent Interactions

Four main types: ionic bonds, hydrogen bonds, van der Waals interactions, hydrophobic interactions

Ionic Bond

Formed by the attraction of oppositely charged atoms or groups of atoms

Cations

Positively charged ions

Anions

Negatively charged ions

Hydrogen Bond

Interaction of a partially positively charged hydrogen atom in a dipolar molecule with unpaired electrons from another atom

Van der Waals Interactions

Weak, nonspecific attractive force between two atoms that approach each other closely

Hydrophobic Interactions

Nonpolar molecules or nonpolar portions of molecules tend to aggregate in water