Lecture 02, 28 Aug 2003 Chapters 2, 3, and 4 Vertebrate Physiology ECOL 437 University of Arizona Fall 2003 instr: Kevin Bonine t.a.: Bret Pasch
Vertebrate Physiology 437 1. 3x5 cards, Syllabus, Photos 2. Vertebrate Physiology Adaptation Homeostasis Feedback Methods 3. Important physical and chemical properties 4. Membranes
Vertebrate Physiology Integration Structure and Function Cells, tissues, organs, organ systems Patterns Principles Illustrative Examples
Adaptation Ecology Evolution (natural selection) Adaptation Adaptation Evolution by natural selection Acclimatization Modification in response to environment within a lifetime (reversibility?) Acclimation (laboratory) Similar to acclimatization but more artificial
Re: Adaptation Plasticity Ontogenetic, environmental
The role of physiology? milieu interior Homeostasis scale?
temperature salinity [glucose] ph [ion] po 2
Regulator temperature salinity [glucose] ph [ion] po 2
Homeostasis (scale) e.g.: Temp. salinity [glucose] ph [ion] po 2
Feedback Loops negative set point (can be reset) homeostasis positive less common -voiding -pregnancy -congestive heart failure -nerv transduction
Scientific Literature
Methods Chapter Two Hypothesis -In the form of a statement -Educated guess (air vs. water, diff t life stages) CO2 is eliminated as bicarbonate ion in tadpoles but as gaseous CO2 in adult frogs. -Testable (experimental design) In chapter 2 you may skip the molecular techniques section (pp; 18-36)
Methods Chapter Two Krogh principle For many physiological questions, there is an animal model ideally suited to answer it. Xenopus eggs Sea raven (fish) heart Giant squid axons Kangaroo rat kidney Horned lizard diet Genetic engineering (diabetic mice, knockouts, obesity, etc.)
B. Organ-level Approaches - Heart in petri dish - Muscle prep in force transducer - Everted sleeve technique for intestinal study e.g. Glucose absorption
C. Organism-level Approaches - Behavior
C. Organism-level Approaches - Metabolism Metabolic Chambers
C. Organism-level Approaches - Metabolism Gas Analysis
C. Organism-level Approaches - Integrative
C. Organism-level Approaches - Physiological State - Sleeping - Resting - Alert - Exercising - Stress-level - Fasting or Fed - Age - Sex - Season - Reproductive Condition - BMR - RMR
Mid-Lecture Question (MLQ) In small groups of about 3 students: How would you design an experiment to test the hypothesis that saltwater crocodiles are osmoconformers? OR How would you ascertain whether or not the extra-long loops of Henle in Kangaroo Rat kidneys were an adaptation to their desert habitat and lifestyle?
Chapter Three - water, molecules, energy, etc. H 2 O - Origins of Life - Universal Solvent - Polar Covalent Bonds - Dipole - H bonds between molecules - transient and weak, but many - high specific heat - surface tension, cohesiveness - Density changes
Water as a Solvent - electrolytes dissociate - Solvation/Hydration -Nonreactive with nonpolar e.g., fats
In Water: - hydrophilic - hydrophobic -amphipathic molecules e.g., micelles Phospholipid bilayers
Solutions: - Colligative Properties Total number of particles -Osmotic Pressure -Freezing Point -Boiling Point - Molarity ( not = molality) 1 M if take 1 mol substance and add water to make 1 L - Osmolarity Sum of colligative particles Dissociation tendency important - 10 mm NaCl with similar osmolarity of 20 mm Glu Strong vs. weak electrolytes (cations and anions)
Ionization of Water, ph Hydronium Ion = H 3 O + Hydroxyl Ion = OH - In 1L pure water at 25ºC, 1.0 x 10-7 of each Equivalent to ph = 7; ph = -log 10 [H + ] Acid (HA) donates a proton Base (A - ) accepts a proton Water can do both, amphoteric Neutral ph (pn) changes with temp: As temp increases pn >7 and vice versa
Mid-Lecture Question (MLQ) In small groups of about 3 students: How is ph important to the biological activity of ionized groups such as amino acids (and their side chains) and proteins (including enzymes)? Part Deux: How do buffers and homeostasis play a role in the above topic?
End
3x5 card Discussion section: 9 (=morning) or 2 (=afternoon) on Wed. Name (and what you prefer to be called) -distinguishing characteristics Email address Year in school Major Relevant courses taken, or research projects, etc. Why are you taking this course? Hold onto card til photo