Biology Lecture Flashcards - Chemistry of Life & Classification

Vocabulary flashcards covering atomic structure, chemical bonds, properties of water, organic compounds, carbohydrates, and domain classification.

Matter

Anything that takes up space and has mass, which is made up of elements.

Plasma

A super charged gas with electrons stripped away, found in the Sun.

Elements

Substances that cannot be broken down into simpler substances; includes 92 naturally occurring elements that serve as building blocks.

BIG SIX

The essential biological elements consisting of Carbon (C), Hydrogen (H), Nitrogen (N), Oxygen (O), Phosphorus (P), and Sulfur (S).

Atom

The smallest unit of an element, composed of subatomic particles: protons, neutrons, and electrons.

Protons

Positively charged subatomic particles found in the nucleus that determine what element an atom is.

Neutrons

Uncharged subatomic particles found in the nucleus.

Electrons

Negatively charged subatomic particles moving around the nucleus, whose outer valence shell determines stability and how the atom will act.

Atomic Number

The number of protons in the nucleus of an atom, shown above the atomic symbol.

Mass Number

The total number of protons plus neutrons in the nucleus of an atom, shown below the symbol.

Octet Rule

The rule stating that main-group atoms tend to gain, lose, or share electrons to reach a total of eight valence electrons in their outermost shell to achieve stability.

Isotopes

Atoms where the number of neutrons is not equal to the number of protons; used in Pt scan diagnostics.

Molecules

Structures formed when two or more atoms bond together.

Compounds

Structures formed when two or more different elements bond together.

Ions

Charged atoms that form when electrons are transferred from one atom to another, creating a charge imbalance.

Covalent Bond

A chemical bond formed when atoms share electron pairs with each other.

Single Bond

A covalent bond resulting from one shared pair of electrons, as in hydrogen.

Double Bond

A covalent bond resulting from two shared pairs of electrons, as in oxygen.

Triple Bond

A covalent bond resulting from three shared pairs of electrons, as in nitrogen.

Ionic Bonds

Bonds formed by transferring electrons from one atom to another, resulting in one positively charged atom (electron lost) and one negatively charged atom (electron gained).

Nonpolar Covalent Bonds

Bonds formed when two atoms share electrons fairly equally.

Polar Covalent Bonds

Bonds formed when two or more atoms share electrons unequally.

Electronegativity

The attraction of an atom for electrons in a covalent bond.

Hydrogen Bonding

A weak attraction between opposite partial charges that causes water molecules to cling to one another.

Organic Molecules

Molecules that always contain carbon and hydrogen, where carbon can bond with 4 other atoms.

Carbohydrate

Biological molecule used for energy.

Glycogen

A polysaccharide (poly) that stores sugar.

Glucose

A monosaccharide (mono) that organisms use first for energy.

Domains

The largest classification category for organisms, comprising Domain Archaea, Domain Bacteria, and Domain Eukarya.

Archaea

A domain of organisms that can survive in major environments.