Comparative Physiology of Animals
(“Environmental Adaptations”)
BISC 437L Catalina Semester 2009
Instructor: Andy Gracey & Jim Moffett, Biological Sciences, USC
Teaching Assistant: Maxine Chaney, Biological Sciences, USC
Course Textbook:
Hochachka & Somero, 2002. Biochemical Adaptation, mechanism and process in
physiological evolution
Oxford University Press
Additional course readings will be handed out in the Journal Clubs.
Course Outline
Many marine invertebrates live in harsh physical and chemical regimes, exposed to
large ranges in temperature, salinity, dessication, and, recently, pollution. This
course investigates how marine invertebrates respond to these stressors at the
molecular and community level. This course will consist of three distinct, but
related, parts -- formal lectures, meetings of the "Journal Club", and laboratory
experiments.
1. Formal Lectures. Monday through Friday. There will be one lecture meeting on
each of these lecture days. Sometimes this first morning meeting will have the
standard lecture format, but it may also have a more informal format (e.g., class
discussion, presentation of class data sets) depending on the progress of the
laboratory experiments during the course.
2. Journal Club. This part of the course will meet Tuesday, Thursday, and Friday.
During each meeting we will discuss papers from the scientific literature that will
be related to the experiments to be undertaken during the course, or elaborate on
themes arising in the lectures. One student will be assigned each paper and that
person will present a summary of the paper to the class and lead the group
discussion. The presentation should be organized as follows: (a) What are the
scientific questions that the paper addresses? (b) What is known about the
question from prior studies? (c) To answer these questions, what data did the
investigators use and how did they obtain the data? (d) What are the results of the
study? (e) Critique of the study. You may find that using a simple PowerPoint
presentation will help you when presenting the paper.
3. Laboratory experiments/field collecting. Monday, Tuesday, and Thursday. All
experiments must be written up. Your TA will inform you of the dates that you are
expected to hand in your laboratory reports (ca. once a week).
Weekly schedule (approximate)
Lecture
Journal Club
Laboratory
Monday
11am
1pm
Tuesday
9am
11am
1pm
Wednesday
9am
Thursday
9am
11am
1pm
Friday
9am
10.30am
Lecture Outline
1.
Introduction to comparative physiology: definitions and terms.
Concept of maintaining homeostasis in different environments.
Introduction to major environmental variables: temperature, water
and oxygen availability, anthropogenic factors, eg. contaminants.
2. Temperature effects on protein stability.
3. Molecular adaptation to heat stress. Role of heat shock proteins in
promoting heat tolerance.
4. Introduction to gene expression and molecular techniques.
5. Adaptation of enzymes to temperature.
6. Adaptation of membranes to temperature.
7. Adaptation to freezing and freeze avoidance strategies.
8. Osmotic regulation: adaptation to seawater, freshwater and
estuarine environments.
9. Adaptation to low oxygen.
10. Midterm exam
11. Introduction to contaminants – what is a contaminant? Toxic
species as contaminants. Nutrients (esp. phosphate) as contaminants.
Concepts of chemical fate and transport.
12. Stress response of marine invertebrates to contaminants,
similarities and differences to physical stressors.
13. Molecular level characterization of stress response.
Metallothioneins, cytochrome p450.
14. Ecological effects. What are the most sensitive organisms?
Invertebrates. The importance of larval stages. Effects of
contaminants on recruitment. Focus on Mytilus edulis.
15. Modes of entry. Bioaccumulation. Classification of contaminants
based on their tendency to bioaccumulate/trophic transfer.
16. Contaminant effects from the molecular to community level: case
studies in polluted regions. Focus on River Fal, UK.
17. More Case studies – South San Francisco Bay, Chanaral, Chile.
18. Predictive toxicology. Quantifying the relationship between stress
response toxicity and contaminant concentration in the lab.
19. Application to environmental protection. How can we use this
knowledge to preserve sustainable ecosystems? Case study –
episodic events (rain/flooding/fire) in Southern California.
20. Final Exam
Grading
50% of your grade will be based on your laboratory write-ups of your experiments
(4 x 12.5%). Some of the experiments that you will be undertaking will be new, in
that we don't know at the outset what kind of data we will obtain (“new” to science,
for the most part). Grading will be based on your careful collection and
presentation of your novel data sets, and your laboratory reports that you will
write in the standard scientific format (Abstract, Introduction, Methods,
Discussion, Literature Cited, Table and Figures). Reports must be typed and should
be approximately 3-5 pages in length (excluding tables and figures). See papers
from journal club for examples.
40% of your grade will be based on a written, comprehensive, midterm and final
examination (15 and 25% respectively). The format of this examination will be
short-answer and long-essay. It will include material from the book, lectures, and
all papers presented in journal club. The test is designed so that you can offer
syntheses and approaches to problems in environmental physiology.
10% of your grade will be based on your presentations in journal club and your
participation in class discussions.
Policies
Missed Exams: Missed exams will receive a grade of zero unless the student has an
excused absence due to a documented medical or family emergency. At the
discretion of the instructor, a missed exam a) may be retaken as a written exam, b)
may be retaken as an oral exam or c) may be given a prorated score based on
performance in the rest of the course.
Regrades: If you would like to contest a grade on an exam or assignment, you must
submit a written explanation of why you think the grade was incorrect. Please note
that the ENTIRE exam or assignment will be subject to reevaluation and your score
may therefore go up, go down or remain the same. Regrade requests must be
submitted to the instructor within two weeks of when the exam/assignment is
returned.
Late assignments: Due dates are written in the schedule. Late assignments will be
downgraded by 10% per day.