BIO 205L

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BIO 205L Laboratory Experiments in Cell
Molecular Biology
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Presentation slides are placed on the web as a
PDF document on the Friday prior to lectures.
This document may be slightly modified during the
following week if an error is detected. The
presentation slides will not always be
comprehensive so be sure to know what is stated
in the lectures. If you wish to print the
presentation slides, then you can save paper by
printing the contents of multiple PDF pages on a
single page.
(for example) 6 pages per sheet
print
file
Page scaling
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Instructors of Record (in order of appearance)
Drs. Jerry Brand, Bill Allen, Enamul Huq

• The Instructors of Record are responsible for
• - the overall operation of the course,
• - providing the Monday lectures,
• - preparing questions for the laboratory entrance
  quizzes and the practical exams at the end of the
  course,
• assigning your final course grade at the end of
  the semester after all course records have been
  assembled and assessed.
• The Course Administrator for this year is Dr.
  Allen

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Laboratory Coordinator Dr. Delia Brownson
The Laboratory Coordinator
- heads a team that prepares and organizes the
equipment and materials for laboratory
exercises, - supervises the overall operation of
the laboratory, - supervises various
administrative issues, - handles authorization of
valid laboratory switches, - assembles and
organizes student attendance records, performance
evaluations and exam grades.
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Laboratory Instructor (teaching assistant)
He/she is your principal teacher and point of
contact. Your Laboratory Instructor will - be
available every week during office hours and by
appointment to assist you in completing the
assignments for the course, - provide
instructions and guidance during your work in the
laboratory, - evaluate your performance every
week on written assignments and in laboratory
work, - assist the Instructors of Record in
determining your final grade for the course.
An experienced undergraduate student will assist
the laboratory instructor during your performance
of the exercises.
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Required Laboratory Manual for BIO 205L
Laboratory Experiments in Cellular and Molecular
Biology
The Manual may be purchased in the Univ. Co-Op on
Guadalupe Street. You must take your laboratory
manual to the laboratory every week. You will not
need to take it to the Monday lectures.
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Where to Obtain Information Pertaining to the
Requirements and the Mechanics of BIO 205L
Announcements and a digital version of hand-outs
are provided during the laboratory or lecture
period. This same information is accessible at
the BIO 205L web site www.sbs.utexas.edu/
bio205L Secure information on the BIO 205L
website can be accessed using Username lt
biosci\bio205L gt Password lt 205Lcell
gt The same username and password access the
laboratory computers. Course announcements will
be posted on the BIO 205L website. They will NOT
be posted in Blackboard.
Extra copies of all BIO 205L student hand-outs
will be kept in a holder just outside of PAI 1.22.
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Monday Lectures
Monday lectures are a required component of the
course. They are not a review or a discussion
section. Topics presented in the lecture each
week are listed on the Course Schedule. The
subject matter presented each week will
complement, but not necessarily repeat, the
chapter reading assignments in the Laboratory
Manual. Attendance will be taken and there will
be a QUIZ during each Monday lecture starting
today, Aug 31st.
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Required For this course

• - CPS (Class Participation System) remote
  controller (available in the Univ. Co-op on
  Guadalupe Street)
• - CPS registration (completed on line via
  Blackboard)
• You should have TWO pad numbers
• one for Monday lectures
• one for your laboratory section

Read and understand the special instructions of
the CPS Use and Rules (a BIO 205L hand-out
provided during your laboratory period) that
pertain to use of the CPS as well as where and
how your CPS scores will be recorded
(eGradebook). You must sign the CPS agreement
that you will abide by the Bio205L CPS Use and
Rules and UTs academic integrity policy.
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Use of CPS for Recording Class Attendance and
Assessing Knowledge of the Subject Matter
Each Monday, starting today, CPS will be used
during the lecture to
- attain a record of attendance, and - allow you
to assess your knowledge of the lectures, reading
assignments and laboratory exercise.
During the J. Brand lectures one question will be
asked near the beginning of the class period,
pertaining to the previous week's lecture. One
or more additional questions will be asked later
in the period, generally pertaining to the
current week's reading assignment and/or written
instructions for the exercise. You should leave
your CPS remote turned on during the entire
lecture so you are ready to answer a question
when it appears.
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Quiz Questions during Lectures
Quiz questions for each Monday lecture period
will be different from the questions asked during
other lecture periods that same day. Quiz
questions must be answered electronically, which
will record your presence in the lecture. You
must not use a calculator, a laptop computer,
notes, or your laboratory manual when answering
quiz questions. Ten percent of your course grade
is based on your lecture attendance and answers
to quiz questions, as determined by your use of
CPS during lectures.
There are no make up lecture quizzes. However,
your lowest two CPS scores will be dropped at the
end of the semester.
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Now we will pause for you to respond to two
questions, using your by CPS remote unit.
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Question 1
Which one of the following reflects your current
status at the University? A. Freshman B.
Sophomore C. Junior D. Senior
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Question 2
Which of the following most closely reflects your
experience in high school biology classes?
A. My biology classes did not have
laboratories. B. We primarily made observations
and/or filled out worksheets in most of my
biology laboratory classes. C. We primarily did
dissections in most of my biology laboratory
classes. D. My biology laboratory classes had
laboratories in which we performed experiments
(involving making measurements or gathering data)
and drew conclusions based upon our results.
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Laboratory Entrance Quizzes
Nearly every week of this course, starting this
week, when the laboratory period starts you will
use your CPS remote to answer several questions.
So be sure to take your CPS remote to the
laboratory every week. Questions for each week's
Laboratory Entrance Quiz will relate to one or
more of the following
a. The subject matter of the Monday
lecture, b. The text reading assignment for the
current week's exercise, c. Information provided
in the exercise for the current week's exercise.
Your answers to Laboratory Entrance Quiz
questions will count 15 of your course grade in
BIO 205L.
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Laboratory Entrance Quiz Questions
The number of questions on Laboratory Entrance
Quizzes may vary from week to week, but quizzes
questions will all be multiple-choice and will
generally not require more than 10 minutes to
complete.
The practice questions provided in today's
lecture are similar in format to the format of
many of the quiz questions.
Quiz questions during this week's exercise will
cover information given in
- today's lecture - lab manual Chapters 1 and 2 -
lab manual Introduction to the Exercises (pp. 185
188) - lab manual Exercise 1 (starting on pg.
189)
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Safety Film
A short video on safety in the laboratory was
shown during last week's laboratory period. All
BIO 205L students are required to have viewed the
safety video before participating in laboratory
exercises. You will not be allowed to
participate in next weeks laboratory exercise,
unless you have seen the safety video this
semester.
The video is less than 20 minutes long.
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Where to obtain BIO 205L course content
information
- your laboratory instructor during laboratory
period - the BIO 205L Laboratory Manual - the
Monday lectures - the BIO 205L web site
ltwww.sbs.utexas.edu/bio205Lgt Username lt
biosci\bio205L gt Password lt 205Lcell gt -
hand-outs pertaining to specific exercises
(Digital copies online and extra copies
outside PAI 1.22)
Your Laboratory Instructor (TA) is your primary
point of contact regarding course content and
your responsibilities in BIO 205L.
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Finally we are ready to start the subject matter
of the course.
- Today we will introduce the topics of this week
and next week exercises. - There will be no
lecture next Monday, Sept 7 (Labor Day) - The
following Monday (Sept. 14) we will consider some
techniques that enhance the quality of
microscopic images.
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From the Bio205L website
http//www.sbs.utexas.edu/bio205L/

• click on Lab Exercise Info button
• Then click on the exercise number to see more
  information for each.

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It is highly recommended that you examine the
information for each exercise every week, PRIOR
to attending your laboratory section.

• For Exercise 1, watch the Instructional Videos
  PRIOR to attending lab.

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Optical Microscopes
A microscope is an instrument for viewing objects
that are too small to be seen by the unaided eye.
An optical microscope (also called a light
microscope) uses light to project a magnified
view of the object.
Some examples of light microscopes
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Illustration of a Simple Microscope (a hand lens)
Although light is shown here passing through the
specimen, hand lenses are more typically used to
focus light is reflected from the surface of an
opaque specimen.
specimen (object)
A hand lens
Image (magnified view of the object)
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Illustration of a Compound Microscope (of the
type typically used to observe living cells)
Compound light microscopes that are used to
observe cells project light through the
specimen. Compound light microscopes that are
used in geological observations reflect light
from the surface of the specimen.
A compound light microscope useful for observing
cells
specimen (object)
Image (twice magnified view of the object)
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Components of a Compound Light Microscope
Observe the image here
Oculars (eyepieces) (contain magnificatIon lenses)
Place object on the stage here
Objectives (Contain magnification lenses)
Focus knobs (raise and lower the stage)
Stage (a movable platform)
light
Condenser (contains lenses that Shape the light
beam)
(not shown) knobs that move the stage laterally
Light source (in base)
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Object The actual specimen that is
observed. Image A (usually magnified)
reproduction of the object.
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Elements of a Compound Light Microscope
eye
path of light
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(No Transcript)
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Light microscopes and electron microscopes appear
very different, but use the same basic
principles of magnification.
A light microscope
An electron microscope
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Four Important Properties of Microscopes
- Magnification - Resolving Power - Aberrations -
Contrast
The qualities of these four properties, taken
together, define the quality of any
microscope. They apply, for example, to light
and electron microscopes.
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First we will consider magnification.
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Magnification of a lens
length of image
Maglens
length of object
2 mm
2 mm
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X


0.1 mm
(2 mm)
image
100 µm
object (100 µm)
no units
recall that 1 mm 1,000 µm
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Total magnification of a compound light microscope
Magtotal Magocular lens X Magobjective lens
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Calculations for Determining Sizes of Objects
Viewed Through a Compound Light Microscope
Definition
length of viewed image
Magtotal

length of object
Rearrange equation
length of viewed image
length of object
Magtotal