Ch. 2 - Chemical Components of Cells

What is the primary chemical component of macromolecules

carbon

What is the universal solvent

water

A compound made of many smaller molecules linked end to end

polymeric compound

Objects that take up space and have mass

matter

The smallest particle of an element that retains its distinctive chemical properties (building blocks of matter)

atoms

an atom cannot be cut without losing its _____

chemical properties

Atoms are linked together to form ____

molecules

Molecules are held together by _____

chemical bonds

What makes up the atomic number

number of protons in nucleus

What makes up the atomic weight

protons and neutrons

An atom with the same number of protons but different number of neutrons is called what

isotope

What is it called when the nucleus disintegrates by radioactive decay

unstable

A chemical bond that involves sharing a pair of electrons between atoms in a molecule

covalent bond

A chemical bond that is formed when one or more electrons are transferred from one atom to another

ionic bond

This type of bond shares 2 electrons and there is free rotation

single bond

This type of bond shares 4 electrons, is shorter and stronger, and is less flexible

double bond

polar covalent bond

A covalent bond in which electrons are not shared equally

A type of covalent bond in which electrons are shared equally between two atoms of similar electronegativity.

nonpolar covalent bond

An atom or molecule with a net electrical charge due to the loss or gain of one or more electrons

ion

Are ionic bonds weaker or stronger than covalent bonds

weaker

electrostatic attraction

attraction between positive and negative charges

When a positively charged region of one molecule comes close to a negatively charged region of a second molecule, the electrical attraction between them can establish a weak bond called ______

hydrogen bond

Substances that dissolve readily in water are termed

hydrophilic

Which substances are hydrophilic

ionic, polar

Substances that contain a preponderance of nonpolar bonds are usually insoluble in water and are termed

hydrophobic

What are important hydrophobic cell constituents

hydrocarbons

These substance are nonpolar, do not form hydrogen bonds, and are generally insoluble in water

hydrocarbons

Substances that release protons when they dissolve in water are termed

acids

Acids are proton _____

donors

Bases are proton _____

acceptors

Molecule that accepts a proton when dissolved in water

base

Which elements make up 96% of an organism's weight

carbon, hydrogen, oxygen, nitrogen

Sets of molecules with the same chemical formula but different structures are called _____

isomers

Mirror-image pairs of isomers are called

optical isomers

Two monosaccharides can be linked by a covalent glycosidic bond to form a disaccharide. This reaction belongs to a general category of reactions termed:

condensation reaction

The most unique function of fatty acids is the formation of the _____ _______, which is the basis for all cell membranes

lipid bilayer

A membrane lipid consisting of a glycerol molecule esteried to two fatty acid chains and a sugar molecule.

glycolipid

Which monomer building block is necessary to assemble selectively permeable boundaries around and inside cells

Fatty acids

The most unique function of fatty acids in cells is the formation of

lipid bilayer

Varied class of molecules with one defining property: they all possess a carboxylic acid group and an amino group, both linked to the same alpha-carbon

amino acids

The covalent linkage between two adjacent amino acids in a protein chain is called a ______

peptide bond

Peptide bonds are formed by what kind of reaction

condensation

What is the name of the amino group at one end of the polypeptide chain

n-terminus

What is the name of the carboxyl group at one end of the polypeptide chain

c-terminus

A nucleoside sporting one or more phosphate groups attached to its sugar is called a ______

nucleotide

Nucleotides can act as what

short term carriers of energy

The most fundamental role of nucleotides in the cell is what

storage and retrieval of biological information

Bases of RNA

A, G, C, U

Bases of DNA

A, G, C, T

Cells contain four major families of small organic molecules, which act as monomers for larger molecules, What are the four:

sugar, fatty acids, amino acids, nucleotides

Two monosaccharides can be linked by a covalent glycosidic bond to form a disaccharide, This reaction belongs to a general category of reactions termed:

condensation reactions

What is the most abundant organic molecule on earth

cellulose

In aqueous solutions, molecules having both polar and nonpolar regions form aggregates called ____

micelles

Name the five amino acids that have a charge

lysine, arginine, histidine, aspartic acid, glutamic acid

Which nucleotide bases are pyrimdines

U, C, T

Which nucleotide bases are purines

A, G

Nucleotides are joined together by what kind of bonds

phosphodiester

The three phosphates in ATP are linked in series by two ______ bonds

phosphoanhydride

A polymer chain is not assembled at random from , instead monomers are added in a particular order called a ____

sequence

Types of noncovalent bonds

electrostatic, hydrogen, van der Waals, hydrophobic

Form of electrical attraction caused by fluctuating electric charges that arise whenever two atoms come within a very short distance of each other

van der Waals attration

A type of weak chemical bond formed when molecules that do not mix with water coalesce to exclude the water.

hydrophobic interaction