Chapter 2

The atom that loses the electron acquires a positive charge becomes a ____________.

Cation

_____________ are ionic compounds that dissociate in water into their components ions when dissolved.

Salts

A chemical bond is ___________________________.

is an energy relationship between the electrons of the reacting atoms.

Hydrogen bonding is responsible for __________________________.

molecular attractions between water molecules that create surface tension.

The pH of 7 is ___________.

neutral

The relative concentration of hydrogen ions is measured in concentration units called ______________.

pH units

The pH scale extends from ______-______.

0-14

Molecule

A combination of two or more atoms

Compound

A combination of two or more different atoms

What are the four molecules unique to living systems, and all contain carbon, making them organic compounds.

Carbohydrates, lipids, proteins, and nucleic acids

______________ also known as proton donors, have a sour taste and dissociate in water to yield hydrogen ions and anions.

Acids

Proteins are long chains of what?

Amino acids connected by peptide bonds

Nonpolar molecules have ____________________________.

An balanced distribution of the shared electrons' charge across the bond

______________ are formed when two monosaccharides are joined.

Disaccharides

The atom that receives the electron takes on a negative charge becomes _________________.

Anion

There are 118 elements recognized; each is designated by one- or two-letter abbreviations called the _________________.

Atomic Symbol

Each element is composed of ________: mostly identical building blocks.

Atoms

__________ also called protons acceptors, taste bitter, feel slippery, and absorb hydrogen ions.

Bases

In the body, ______________ are primarily used as an energy source.

Carbohydrates

_______________ are a group of molecules, classified as either monosaccharides, disaccharides, or polysaccharides, that contain carbon hydrogen and oxygen. Including sugars and starches.

Carbohydrates

___________________ are heterogeneous mixtures that often appear milky and have larger solute particles that do not settle out of solutions.

Colloids (Emulsions)

______________________ occur when pairs of atoms share electons, and atoms may share one, two, or three pairs of electrons, forming single, double, or triple bonds.

Covalent Bonds

______________ is the genetic material of the cell and is found within the nucleus.

DNA

all ions are called _________ because they can conduct electrical currents in solution

Electrolytes

__________ occupy random positions within orbitals surroundings the nucleus, have a negative charge, and a weighless 0 atomic mass units.

Electrons

________________ are globular proteins that act as biological catalysts, enabling biological processes to happen quickly enough to support life.

Enzymes

The _____________________ may be either saturated, having only single bonds between adjacent carbons, or unsaturated, bearing at least one double bond between a pair of carbons in the chain.

Fatty Acids

_____________ are extended, strand-like, insoluble molecules that provide mechanical support and tensile strength to tissues.

Fibrous proteins

______________ are compact, spherical, water-soluable, and chemically active molecules that oversee most cellular functions.

Globular proteins

The structure of proteins have how many structural levels?

Four

The greater the concentration of hydroxyl ions, the more basic or alkaline, the solutions meaning the pH value is ____________. A.)higher B.) lower

Higher

_______________ are responsible for stabilizing the three dimensional shapes of large molecules.

Hydrogen Bonds

______________________ are formed when a hydrogen that is covalently bonded to one atom (often oxygen or nitrogen) is attracted to another electronegative atom, forming a sort of "bridge."

Hydrogen Bonds

Each element has ___________, structural variations of an atom that have the same number of protons, but different numbers of neutrons.

Isotopes

The most ionic compounds for salts, and when dry, form dry form crystals that are held together by ________________.

Ionic bonds

___________________ are chemical bonds that form between two atoms that transfer one or more electrons from one atom to the other.

Ionic bonds

Water is important because _______________________.

Its a reactant in many chemical reactions.

The __________ sequence of amino acids is the primary structure.

Linear

___________________ are insoluble in water, but dissolve readily in non-polar solvents, and include triglycerides, phospholipids, steroids, and other lipoid molecules.

Lipids

The greater the concentration of hydrogen ions in a solutions, the more acidic the solutions meaning the pH value is ___________. A.) higher B.) lower

Lower

Mixtures

Mixtures consist of two or more substances that are physically mixed

___________________ are simple sugars, named for the number of carbons they contain, that are single-chain or single-rings structures.

Monosaccharides

Neutrons have _____________ charge.

No charge

Covalent bonds may be ________, sharing their electrons equally.

Non-polar

______________ have two primary classes: deoxyribonucleic and ribonucleic.

Nucleic Acids

______________ are the structural units of nucleic acids, and consist of three components: pentose sugar, a phosphate group, and a nitrogen-containing base.

Nucleotides

______________________ are diglycerides with a phosphorus-containing group and two fatty acid chains that are primarily used to construct cell membranes.

Phospholipids

Covalent bonds may be ________________, sharing their elections unevenly.

Polar

In _______________________, electrons are more attracted to one atom (an electronegative atom) than the other (an electropositive atom,) resulting in the area of the bond closest to the electropositive atom takes on a partial positive charge.

Polar Molecule

__________________ are long chains of monosaccharides linked together by dehydration synthesis; two biologically important, polysaccharides are starch and glycogen.

Polysaccharides

Protons have a ________ charge.

Positive

_______________ is a loss of the specific three-demensional structure of a protein, leading to a potential loss of function, that may occur when globular proteins experience changes in environmental factors such as temperature and pH.

Protein Denaturation

_____________ are the basic structural material of the body and play vital roles in cell function

Proteins

Each atom has a central nucleus made up of ___________ and _____________.

Protons and Neutrons

Elements are identified based on their number of ___________, ____________, and _____________.

Protons, neutrons, and electrons.

______________ structure results from two or more polypeptide chains grouped together to form a complex protein.

Quaternary

____________________ may be described by their concentrations, often expressed as a percent, or molarity.

Solutions

The substance present in the greatest amount (usually a liquid) is called ______________, while substances dissolved in the ________ are called Solutes.

Solvent

The mass number of an element is equal to _______________________________.

The number of the protons plus the number of neutrons.

__________, including cholesterol, are flat molecules made up of four interlocking hydrocarbon rings and are used in the body in cell membranes and hormones.

Steroids

___________________ are heterogenous mixtures with large, often visible solutes that will settle out of solutions.

Suspensions

Half-Life

The time for a radioisotope to lose one-half of its radioactivity.

_______________ are called neutral fats consist of glycerol (a sugar alcohol), and fatty acids.

Triglycerides

________________ forms a protective cushion around organs of the body.

Water

_________________ is the most important inorganic molecule, and makes up 60-80% of the volume of living cells.

Water

The Nucleus has a ______________ charge.

a net positive

Proteins twist and turn on themselves to form

a secondary structure; either spiraled helixes or pleated sheets

When a pH is considered basic or alkaline, it is what, on the pH scale?

above 7

Water has a high heat capacity, meaning it _________________________.

absorbs and releases a great deal of heat before it changes temperature.

Radioisotopes are _________________________.

are heavier, unstable isotopes of an element that spontaneously decompose into moree stable forms, producing radioactivity.

When a pH is considered acidic, it is what, on the pH scale?

below 7

A _______________ is combination of a weak acid and weak base that resists large fluctuations in pH that would be damaging to living tissues by releasing H+ when pH rises, and binding up H+ when pH drops.

buffer

What four elements make up roughly 96% of body weight?

carbon, hydrogen, oxygen, and nitrogen.

Solutions

solutions are homogenous mixtures of compounds that may be gases, liquids, or solids.

The ____________ structure is resulting from protein folding upon itself to form a ball-like structure.

tertiary

The atomic number of an element is equal to _______________________; _____________________.

the number of protons of an element; the number of electrons always equals the number of protons.

Water, called the _____________________, is a polar molecule that plays a role in dissociation of ionic molecules, forms hydration layers that protect charged particles, and functions as an important transport medium in the body.

the universal solvent

The atomic weight of an element is a weighted average of ____________________________, based on their relative abundance in nature.

the weight's mass numbers of all known isotopes of an element

What five nitrogen bases are using in nucleic acids.

two-larged, double ringed purines, adenine (A), and guanine (G) and three smaller, single-ringed pyrimidines, cutosine (C), uracil (U), and thymine (T).

Water has a high heat of ________________, meaning that ittajes a great deal of energy (heat) to break the bonds between water molecules.

vaporization