Anatomy Ch.2
carbon dioxide
a wast product of metabolic processes and exhaled from the lungs
elements
all matter is composed of fundamental substances called _____
chemicals
all the food that we eat, liquids that drink and medications that we take are _____
false
an acid is defined as an electrolyte that releases hydroxyl ions in water and an example is sodium hydroxide
true
an atom that has gained or lost electrons is called an ion
false
an element with an atomic number of 6 contains 12 protons
hydrolysis
another name for the chemical digest not polymers is ____
electrolytes
as a group, compounds that release ions when they dissolve in water are called _______
gets smaller
as hydrogen ion concentration increases the pH number ___
elements
at present, there are 90 naturally occurring ____-
ions
atoms that gain or lose electrons become electrically charged and are called ___
false
buffers combine with hydrogen ions when they are in excess or they donate hydroxide ions when they are depleted
compound
when atoms of different elements bond, they form molecules called _____
true
when two or more atoms bond, they form a new kind of particle called a molecule
carbon
which of the following chemicals is not an inorganic substance
carbon dioxide
which of the following is not an organic substance
carbon, hydrogen, oxygen, nitrogen
which of the following substances comprise 95% of the human body
atp
which of the following substances is not an element
fats
____ are used primarily to store energy for cellular activities
buffers
_____ are chemicals that resist changes in pH
decomposition
_____ reaction is symbolized as AB -> A+B
nucleotides
______ are the building blocks of nucleic acids
nucleic acids
______ include the molecules known as DNA and RNA
synthesis
a ____ reaction is symbolized as A+B-> AB
exchange reaction
a chemical reaction in which pairs of two or more different molecules trade positions with one another is an ________
false
a covalent bond is formed by two atoms that exchange electrons
true
a molecular formula represents the number and types of atoms in a molecule
atoms
a molecule of a compound always contains definite kinds and numbers of _____
7
a pH of __ is the midpoint of the pH scale and contains equal numbers of hydrogen and hydroxide ions
rises above 7.45
a person has alkalosis if the good pH ________
acidic
a solution that contains more hydrogen ions than hydroxide ions is ____
basic
a solution that contains more hydroxide ions that hydrogen ions is _____
7
a solution that has a pH of 6 has ten times the hydrogen ion concentration of a solution with a pH of __
electrolytes
a substance that ionizes in water
false
a substance that releases hydrogen ions in water is a base
true
chemistry is the branch of science that studies the composition of matter
false
cholesterol is a protein that is used by the body to make sex hormones
10 fold
each number on the pH scale represents a ________ difference in hydrogen ion concentration
atoms
elements are composed of tiny particles called _____
false
if the bonds within a reactant molecule break so that simpler molecules, atoms or ions form, the reaction is an exchange reaction
true
if two pairs of electrons are shared, the resulting bond is called a double covalent bond
true
inorganic substances dissociate in water to release ions
true
matter is anything that has weight and takes up space
pH
measures hydrogen ion concentration
true
oxygen is used by cellular organelles to release energy from glucose
structural formulas
show how atoms are joined and arranged in various molecules
electrons
sodium & chloride ions combine readily because they both tend to lose or gain ____
false
the atomic weight of an atom of an element equals the number of neutrons in its nucleus
false
the atomic weight of an atom of an element equals the number of protons and neutrons in its nucleus
neutrons
the atoms of the isotopes of a particular element vary in number of ____
hydrogen bond
the attraction of the positive end of a polar molecule to the negative nitrogen or oxygen end of another polar molecule is called a _______
false
the building blocks of fat molecules are amino acids
true
the building blocks of proteins are amino acids
proteins
the different types of carbohydrates do not include
shells
the electrons of an atom occupy one or more areas of space called
2 electrons
the first electron shell of an atom can hold a maximum of _____
a molecule contains 2 hydrogen atoms and 1 oxygen atom
the formula H2O means
atomic number
the number of protons in the atoms of a particular element is called _____
0-14
the pH scale ranges from __ to ___
neutron
the parts of an atom that lack an electrical charge are called ______
covalent bond
the type of chemical bond formed when atoms share electrons is called _______
true
the value called pH measures the hydrogen ion concentration in solutions such as body fluids
chemical changes
understanding chemistry is essential for understanding a&p because body structures and functions result from _____
true
water accounts for 2/3 of the weight of an adult human
true
water is an example of a compound
electrons
when atoms combine with other atoms, interactions occur between their _____
