Anatomy & Physiology 34A Lecture
Chapter 2 – Chemistry Comes Alive: Basic Chemistry
I. Overview
A. Matter & Energy
B. Elements & Atoms
C. Molecules & Bonds
D. Solutions & Solutes
E. Chemical Reactions
II. Matter & Energy
A. ____________ is anything that takes up space and has _______; it can be solid, liquid, or
gas; all matter is composed of __________
B. ___________ is the capacity to do work. Two types of energy are:
1. ___________ energy – stored energy or energy of position
2. ________ energy – energy of movement; active working energy
C. Forms of energy involved in body functions are chemical, electrical, light, and
mechanical. Of these, _____________ (bond) energy is most important
D. Energy may be ____________ from one form to another, but some of the energy is always
lost as ________
III. Elements & Atoms
A. An element is a substance that contains just one type of ________
1. The most abundant ____________ (96% of wt.) in the body are:
a.
b.
c.
d.
2.
Carbon
(___)
Hydrogen
(___)
Oxygen
(___)
Nitrogen
(___)
Lesser elements (__________) make up about 4% of body wt.:
a. Calcium
(___)
b. Phosphorous (___)
c. Magnesium (___)
d. Sodium
(___)
e. Potassium
(___)
f. Chlorine
(___)
g. Sulfur
(___)
h. Iodine
(___)
i. Iron
(___)
3. _________ elements are only about 0.01%, but are also essential
a. They include chromium (___), Cobalt (___), Copper (___), Fluorine (___), Lithium
(___), Manganese (___), Molybdenum (___), Selenium (___), Silicon (___), Tin
(___), Vanadium (___), and Zinc (___)
b. Trace elements often serve as ______________ in enzymes
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C. Periodic Table of Elements Organization
1. Horizontal _______ are arranged by atomic number (number of protons) & mass
(protons + neutrons)
2.
Vertical _____________ are arranged by no. of electron orbitals
D. ________ - Smallest unit of matter involved in chemical reactions. An atom consists of:
1. _____________ - atom center composed of protons & neutrons
a.
b.
c.
d.
________ (p+) has positive (+) charge; atomic mass of 1 amu
b.
Highest ________ electrons (valence electrons) are located in orbitals farthest
from the nucleus, and react with other atoms
c.
An electrically __________ atom has # electrons = # protons
__________ (no) has no charge; atomic mass of 1 amu
Atomic ____________ = number of protons
Atomic ________ = number of protons + neutrons
2. __________ (e-) has a negative (-) charge and negligible weight
a. Electron Orbitals (shells)
1) The innermost orbital contains up to ____ electrons
2) Each outer orbital contains up to ___ electrons
3) Atoms are most stable when they have ____ electron shells
E. _______________ - atom with same # of protons and electrons as another atom of the
same type, but with a different # of _________ (e.g., 14C vs. 12C)
1.
2.
Radioactive isotopes break down (_______) and emit radioactive particles
Radio____________ are used in medicine to diagnose and treat some diseases
F. ________ are atoms that have gained or lost electrons, giving them and overall negative or
positive charge
1. __________ gain electrons, thus have a __________ charge (e.g., Cl-)
2. __________ lose electrons, thus have a __________ charge (e.g., Na+)
3. _________ dissolve in water to form ions.
G. A Free ________ is a particle with an unpaired electron (e.g., O2-.)
1. Free radicals disrupt other molecules in the body by taking ___________ from them
2. ______________, such as vitamins A, C, and E, neutralize free radicals by donating
electrons without becoming free radicals.
IV. Molecules & Bonds
A. _____________ - Two or more atoms covalently bonded together
(e.g., O2, N2)
B. _____________ – substance that contains two or more different elements, whose atoms
are chemically bonded (e.g., CO2, H2O).
C. Four types of ________ join atoms: ionic, covalent, and hydrogen bonds, and Van der
Waals forces
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D. ___________ Bond - strong attraction between negatively and positively charged
_______
1.
In ionic reactions, atoms ______ or ______ electrons to get a full outer electron
orbital
2. Oppositely charged ions are strongly attracted to each other, form ionic bonds, and are
called ________ or electrolytes (e.g.: NaCl)
E. ____________ Bonds are strong chemical bonds between atoms that result from the
__________ of electrons in their outer orbitals.
Molecules with covalent bonds may be represented as::
1.
______________ formulas in which each pair of shared electrons is represented by a
line (e.g.: O=C=O).
2.
________________ formulas that show only the number of each type of atom in the
molecule (e.g.: CO2)
a. Molecular formulas can be used to calculate ___________ ________ by
multiplying the atomic mass of each element in the molecule by the number of
atoms in the molecule, then adding the results
b. Calculate the molecular wt. of glucose (C6H12O6), where C = 12 amu, H = 1 amu,
and O = 16 amu
3.
______________ molecules are those whose atoms share their electrons equally, thus
do not have an overall charge (e.g., CO2)
4.
_____________ molecules are those in which some atoms in the molecule attract the
shared electrons more strongly, thus the molecule has partial positive and negative
charges (e.g., H2O)
E. ____________ Bonds are weak bonds between a slightly positive hydrogen atom and a
slightly negative oxygen (e.g., in H2O) or nitrogen atom (e.g., in DNA)
F. ____ der _______ forces are very weak bonds that result from the attraction of one atom’s
nucleus to the electrons of another atom
V. Mixtures & Solutes
A. __________ have two or more components physically intermixed. Three types of
mixtures are solutions, colloids, and suspensions
1. ___________ – mixtures with tiny particles (_______) dissolved in a _________
(usually water). The solvent and solute may be gas, liquid, or solid.
2. _____________ – have larger solute particles (often proteins) suspended in the
mixture (e.g.: jello and a cell’s cytosol)
3. _____________ – have even larger, often visible, solutes that precipitate (settle) out
of the mixture (e.g.: blood)
B. _______________ of solutions can be expressed several ways
1. Moles & Molarity
a. ________ – a large number of particles equal to 6.02 x 1023
b. _______ molecular ________ is the atomic mass or molecular weight of a substance
in grams. Example: the molecular wt. of glucose (C6H12O6) is 180 amu, so one
mole glucose = 180 g
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c. Molarity is the number of _______ of solute in a liter of solution (mol/L or M).
1) A one molar solution of glucose would be made by dissolving ______ g (one
mole) of glucose in enough water to make 1 _________ total
2) Biological solutions are so dilute, they are usually expressed in
_______________ per liter (mmol/L or mM)
2. _______________ (eq) – the molarity of an ion times the number of charges it carries.
a. Examples: Na+ would have ___ equivalent per mole; Ca2+ would have ___
equivalents per mole
b. Concentration of ______ in the blood are often expressed in ______equivalents per
liter (meq/L)
3. Weight per Volume and Percent Solutions
a. Percent solution - the _________ of _________ in the total solution.
b. If the solute is _________, the percent solution is expressed as _______/volume.
Example: a 5% solution of glucose is made by mixing 5 g glucose with enough
water to make 100 ml
c. If the solute is ____________, the solution is made using _______/volume
measurements. Example: to make 0.1% HCl sol’n, mix 0.1 ml concentrated HCl
with water to make 100 ml
d. Concentrations of drugs and chemicals in the body are often given in milligrams per
__________ (mg/dl). A deciliter is 100 ml.
VI. Chemical Reactions – processes by which chemical ________ are broken or formed
A. Chemical _____________ - represents the course of a chemical reaction Example:
CH3CH2OH + O2  CH3COOH + H2O
(Ethanol + Oxygen  Acetic acid + Water)
1. ____________ are substances that enter into a reaction
2. ____________ are substances produced by the reaction
3. ____________ chemical equations have the same number of each type of atom on both
sides of the equation
B. __________ of reactions include decomposition (catabolism), synthesis (anabolism), or
exchange reactions
1. In ___________ reactions, a large molecule breaks down into 2 or more smaller ones
(AB  A +B) (e.g., starch to glucose). Most catabolic reactions are ___________ –
they release energy
2. In __________ reactions, 2 or more small molecules combine to form a larger one (A +
B  AB) (e.g., amino acids to proteins). Most anabolic reactions are ___________ –
they require energy.
3. In _________ reactions, 2 molecules exchange atoms or groups of atoms (AB + CD 
AC + BD)
(e.g., NaHCO3 + HCl  NaCl + H2CO3)
C. _______________ Reactions can go in either directions under different conditions, and
are represented by 2-headed arrows:
CO2 + H2O  H2CO3  HCO3- + H+
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1. Reversible reactions follow the law of _______ ________, they move from the side
with more reactants to the side with less reactants
2. Reversible reactions normally exist in a state of _____________, in which the ratio of
products to reactants is relatively stable
D. Oxidation/Reduction (________) chemical reactions
1.
______________ = loss of electrons (or hydrogen); exergonic reaction; atoms that
have lost electrons have _____ energy.
2.
______________ = gain of electrons (or hydrogen); endergonic reaction; atoms that
have gained electrons have ______ energy.
3. In redox reactions, one or more molecules give up electrons (become ____________)
and one or more molecules gain the electrons (become ______________)
4. ________ is often the oxidizing agent (hence the term oxidation)
5. Example: Cellular ___________ involves a series of redox rxns. C6H12O6 + O2 ---
6CO2 + 6H2O + ATP
E. Reaction ______, how fast a reaction proceeds, are influenced by:
1. _____________ – greater temp. = faster rate
2. ________________ – greater reactant concentration = faster rate
3. Particle _______ – smaller particles move faster, collide more frequently, causing
rapid reactions
4. _____________, such as enzymes, speed up reaction rates