the chemical level of organization chapter 2 A&P
the atomic weight of carbon is
12
how many electrons are needed to fill carbons outer shell?
4
the atomic number of carbon is
6
an example of a synthesis reaction is
A+B --> AB
an example of an exchange reaction is
AB + CD --> AD + CB
the most important high- energy compound in cells is
ATP
the symbol for the carbon atom is
C
which of the following molecules is drawn correctly to show the proper covalent bonding?
H-O-H
a decomposition reaction is one in which
a molecule is broken down into smaller fragments
proteins consist of long chains of small molecules called
amino acids
a solute that dissociate to release hydrogen ions and causes a decrease in pH is
an acid
the activation energy requirement of a reaction is much lower in the presence of
an appropriate enzyme
synthesis of new compounds in the body
anabolism
the smallest units of matter whose identities cannot be altered by a chemical change are
atoms
a solute that removes hydrogen ions from a solution is a
base
stabilize pH
buffer
compounds that stabilize pH by either removing or replacing hydrogen ions are
buffers
organic compounds differ from inorganic compounds in that organic compounds are primarily composed of
carbon and hydrogen atoms and are much larger and more complex
decomposition reaction within cells
catabolism
enzymes belong to a class of substances called ___, which accelerate chemical reactions without themselves being permanently changed
catalysts
positively charged ion
cation
ions with a positive charge are called
cations
___, the functional units of life, are made of a variety of biochemicals
cells
the number and arrangement of electrons determine the
chemical behavior of an atom
is carbon inert or chemically active?
chemically active
any chemical substance made up of atoms of two or more elements, regardless of how the atoms achieve stability, is a
compound
atoms that complete their outer shells by sharing electrons with other atoms result in molecules held together by ____
covalent bonds
soluble inorganic compounds whose ions will conduct an electric current in solution are
electrolytes
a chemical _____ is a substance that consists entirely of atoms with the same atomic number
element
carbohydrates are most important to the body because they serve as sources of
energy
acts as catalyst to speed up chemical reaction
enzymes
special proteins that catalyze reactions involving specific substrates are called
enzymes
shuffling around of reacting molecules
exchange reaction
exergonic reactions, which are common in the body, are responsible for
generating the heat that maintains your body temperature
the monosaccharide that serves as the most important metabolic fuel molecule in the body is
glucose
the polysaccharide formed by stored glucose in the liver and muscle is
glycogen
______ bonds are too weak to create molecules, but they can alter molecular shapes or pull molecules together
hydrogen
acids, bases, and salts are examples of ___ compounds
inorganic compounds
when one atom loses an electron and another accepts that electron, the result is the formation of an
ionic bond
the attraction of cations to anions can lead to the formation of
ionic bonds
during ___, water molecules disrupt the ionic bonds of a solute and a mixture of ions is produced
ionization
two atoms of same element with different number of neutrons
isotope
energy of motion
kinetic energy
the protons and neutrons of an atom determine the
mass number of an atom
when a chemical reaction occurs, the chemical structures that contains more than one atom are called
molecules
each amino acid differs from others in the
nature of the R group
isotopes of an element differ in the number of
neutrons in the nucleus
the synthesis of all cellular protein is directed by
nucleic acid
the molecules that store and process information at the molecular level are the
nucleic acids
most high- energy compounds are derived from
nucleotides
the center of atom is called the ____
nucleus
compounds that contain the elements carbon, hydrogen, and usually oxygen are ____ compounds
organic compounds
the attachment of a carboxylic acid group of one amino acid to the amino acid group of another forms a connection called a
peptide bond
removing a ___ group from a high energy compound releases energy that can be used by the cell to do work
phosphate
the most abundant lipid components of cell membranes are
phospholipids
unequal sharing of a pair of electrons between two atoms forms a
polar covalent bond
stored energy
potential energy
the chemicals that form an internal supporting framework and act as enzymes to accelerate and control the chemical reactions that maintain homeostasis are
protein
the subatomic particles found in the nucleus of an atom include
protons and neutrons
the atomic number represents the number of
protons in an atom
the three subatomic particles that are stable constituents of atomic structures are
protons, neutrons, and electrons
when an enzyme promotes a chemical reaction by lowering the activation energy, it only affects the
rate of the reaction
a ___ is an ionic molecule containing any cation (except H+) and any anion (expect OH-)
salt
butter, fatty meat, and ice cream are examples of sources of fatty acids that are said to be
saturated
an example of a buffer in the body is
sodium bicarbonate
dissolved material in solution
solute
most chemical reactions in the body take place in
solution
liquid portion of solution
solvent
special molecules called enzymes found in cells
speed up the reactions that support life
a lipid consisting of four connected rings of carbon is a
steroid
the substance that is acted upon by an enzyme
substrate
the three basic components of a single nucleotide of a nucleic acid are
sugar, phospate group, and nirtogenous base
inorganic ions are important in the functions of
the heart, muscle contractions, and nerve impulse conduction
the most common fats found in the human body are in the form of
triglycerides
the symbol 2H means
two atoms of hydrogen
the nitrogen base found in RNA but not in DNA is
uracil
the most important inorganic compound found in large quantity in the body is
water