Biology Ch. 2 The Chemical Foundation of Life

___ have the same covalent arrangements but differ in spatial arrangements.

Living organisms require ___ more than any other substance.

The more strongly a atom pulls shared electrons towards itself, ________________.

Substance consisting of 2 or more elements in a fixed ratio.

___ makes large, complex molecules possible.

Radioactive isotopes decay spontaneously, giving off ___.

Substance that cannot be broken down to other substances by chemical reaction.

Water ___ heat from warmer and ___ stored heat to cooler air.

A charge atom/molecule is an ___.

Attraction between molecules that are close together as a result of these charges.

Water reaches its greatest density at __

Cells are 70%-95% water, the rest are mostly of carbon-based compounds.

What is the main reason that Earth is habitable?

Carbon chains __ in length and shape.

Lake __ in the summer and ___ in the spring and fall.

A ___ substance is one that does not have an affinity for water.

Matter is made up of ___.

Cells themselves are ___ water.

The sharing of a pair of valence electrons by two atoms.

With 4 valence electron, carbon can form __ covalent bonds with a variety of atoms.

A molecule's shape is determined by the positions of its atoms' valence orbitals.

___ are isomers that are mirror to each other.

Compounds formed by ionic bonds are called ___.

Number of protons in a nucleus.

___ is the biological medium on Earth.

An atom's attraction for the electrons in a covalent bond.

Surfactants are __ molecules that break the surface tension.

A positively charged ion.

Water can absorb/release a lot of heat with a slight change of temperature.

Covalent bonds ___ most of a cell's molecule.

Anything that takes up space and has mass.

Heat is __ when hydrogen bonds break; ___ when hydrogen bonds form.

___ measures the intensity of heat due to the average kinetic energy of molecules.

Concentrations of H⁺ and OH⁺ are ___ in pure water

___ is the measure of the total amount of kinetic energy due to molecular motion.

Oil molecules are __ because they have relatively nonpolar bonds.

___ are attached to skeletons of organic molecules

Living organisms are subject to basic laws of ____.

Atoms share the electron equally.

Organic molecules consisting of only carbon and hydrogen.

Many organic molecules, such as fats, have hydrocarbon components.

Atoms of an element that differ in number of neutrons.

Sum of protons plus neutrons in the nucleus.

Water resist changing its temperature because of its ____.

Ice floats in liquid water because hydrogen bonds in ice are more "__", making ice ___ dense.

The promotion of unsubstantiated methods that lack a scientific plausible rationale.

Rain, snow, or fog with a pH lower than 5.6.

A molecule's shape is usually ___ important to its function.

___ is attraction of water with different substances.

Large polar molecules such as proteins can dissolve in water if they have ____.

___ have different covalent arrangements of their atoms.

Shared electrons count as part of each atom's valence electrons.

One atom is more electronegative, and the atoms don't share the electron equally.

Carbon chains form the ___ of most organic molecules.

Two enantiomers of a drug have the same effect.

___ cells are surrounded by water.

Small changes in functional groups have minimal effects on biological function.

Water's high specific heat can be traced to hydrogen bonding.

Atoms of different elements have the same number of subatomic particles.

Hydrocarbon undergo reactions that release a large amount of ___.

___ reinforce shapes of large molecules and help molecules adhere to each other.

A negatively charged ion.

Hydrogen bonds hold water molecules together.

A ___ substance is one who has an affinity for water.

Polarity allows water molecules to form ___ with each other.

Atom's total mass, can be approximated by the mass number.

____ is a measure of how hard it is to break the surface of a liquid.