AP Biology at Bensalem High School
With
Ms. Gallagher
A Little about Advanced Placement
 Courses are designed by “The
College Board” To emulate
freshman college courses
 AP Test covers the entire year of
work
 AP BIOLOGY is an 8 credit
course. That is two semesters of
college-level work
 Most colleges and universities
award students 8 credits if they
achieve a 4 or 5. Some colleges
accept a 3 for nonscience majors
The Exam

May 14, 2012

100 Multiple Choice Questions

4 Free Response Questions

3 hour exam

Cost: Approx. $85.00
AP BIO AT BHS
 Laboratory-intense, Inquiry-based
 We will perform 24 freshman college
laboratories
 Text: Campbell’s Biology, 7th/9th ed.
We will complete the entire book, 55
chapters. Entire text is available
online at “ The Campbell Place”
 Resources: Students have a book of
notes, a study guide, a textbook,
and laboratory manual

Additional resources: Campbell’s Biology
on-line has animations, self quizzes, and
lecture outlines.

College Board: Published exams for one
year and many years of free response
questions.
Grading
 Homework/Classwork – 15%
 Laboratory Work and Lab
Quizzes – 30%
 Tests and Essays – 55%
 The AP TEST will count as your
final. If you are not taking the
test, you will need to take a first
and second semester final exam
 EXTRA CREDIT: Students who
participate in PJAS will receive
extra credit in the third marking
period.
WORK LOAD

Students are expected to spend at least one
hour every night on AP BIO.

And more time to prepare for the exam in
May.
Contacting me:

kgallaghe@bensalemsd.org

Or 215-750-2800 ex: 3054

Wikispaces:

http://bhsgallagher.wikispaces.com
Field Trip

Suggestions?

We’ve done the Zoo for the last several years.
Chemical Bonding

Covalent

Double covalent

Nonpolar covalent

Polar covalent

Ionic

Hydrogen

van der Waals forces
Covalent Bonding
 Sharing pair of valence
electrons
 Number of electrons
required to complete
an atom’s valence
shell determines how
many bonds will form
 Ex: Hydrogen &
oxygen bonding in
water; methane
Polar/nonpolar covalent bonds
 Electronegativityattraction for
electrons
 Nonpolar covalent •electrons
shared equally
 •Ex: diatomic H2 and O2
 Polar covalent
 •one atom more electronegative than
the other (charged)
 •Ex: water
Ionic bonding
 High electronegativity
difference strips valence
electrons away from another
atom
 Electron transfer creates ions
(charged atoms)
 Cation (positive ion); anion
(negative ion)
 Ex: Salts (sodium chloride)
Ionic bonds
Hydrogen bonds
Hydrogen atom
covalently bonded to
one electronegative
atom is also attracted
to another
electronegative atom
(oxygen or nitrogen)
Chemical Bonding: Importants points are ???
Ionic Bonds
Covalant Bonds
Polar
Nonpolar
Hydrogen
van der Waals interactions
 Weak interactions between
molecules or parts of
molecules that are brought
about by localized charge
fluctuations
 Due to the fact that electrons
are constantly in motion and at
any given instant, everchanging “hot spots” of
negative or positive charge
may develop
Water
 Polar: opposite ends, opposite
charges
 Cohesion: H+ bonds holding
molecules together
 Adhesion:H+ bonds holding
molecules to another substance
 Surface tension: measurement of the
difficulty to break or stretch the
surface of a liquid
Special Characteristics of Water
•Specific heat: Amount of heat absorbed or
lost to change temperature by 1oC
•Heat of vaporization: Quantity of heat
required to convert 1g from liquid to gas
states
•Density:Solid state less dense than liquid
Density
 Less dense as solid
than liquid
 Due to hydrogen
bonding
 Crystalline lattice
keeps molecules at
a distance
Acid/Base & pH
 Dissociation of water into a hydrogen
ion and a hydroxide ion
 Acid:
increases the hydrogen
concentration of a solution
 Base:
reduces the hydrogen ion
concentration of a solution
 pH:
“power of hydrogen”
pH Determination:

Water : Mostly HOH molecules

Very few H+ ions and OH- ion

More H+ = Low pH = Acidic

More OH- = High pH= Basic

pH scale is exponential ( Like seismic waves )

pH + pOH = 14

pH = - log [H+], pOH = - log [OH]

pH = exponent in the [H+]
Complete the Chart
[H+]
10-7
[OH-]
pH
10-7
4
10-8
11
Acidic/Basic/Neu
tral ?
Review Questions
1. How does water stabilize global temperature ?
2. How does sweating help maintain your temperature?
3. Temperature is a measure of ? ______________
4. How much more acidic is a solution with a pH of 2 versus one
with a pH of 4 ? _______________
5. What is a buffer? Why are they important?
6. How would you make a 0.1 M solution of glucose?
7. Sketch a water molecules showing its shape and the electron shells
with the covalently shared electrons. Indicate the areas with slight
negative and positive charges that enable a water molecule to form
hydrogen bonds.