Bio 120 Test #5, Fall 2015
Wednesday, Dec 9, 8:00-9:45
Ch. 19- Genetic Drift (403-406) and Patterns/Modes of Natural Selection (397-401)
Basic terms: alleles, population, evolution, adaptation
What is genetic drift? How does it compare/contrast to natural selection?
Random loss of alleles, random survival, right time/right place
Basic outcomes of drift
Quick, random, non-adaptive evolutionary change (Fig. 19.19)
Loss of genetic diversity/Genetic Bottleneck (Fig. 19.20)
Founder Effect- quick increase in frequency of formerly rare allele- why?
Applications to conservation
Fixing habitat loss and population size insufficient for long-term conservation
Small populations and genetic deficits/How do drift and natural selection interact?
Reduced variability, decreased potential for adaptive evolution
Genetic rescue
Directional selection- against one extreme because of directional env change (Fig. 19. 12)
Diversifying/Disruptive selection- for both extremes (Fig. 19.14)
How does intra-specific competition drive disruptive selection?
Disruptive selection and speciation/cladogenesis
Stabilizing- probably most common type of selection, but also most subtle (Fig. 19.13)
Clutch size in birds, human birth weights- effects of medical technology
Problems: 2, 10; Collaborative 1
Ch. 27- Plant Structure & Function (574-577, 583-586)
Morphology- study of how structure and function are related, body size, thermoregulation
SA vs vol: selection for diversity in body sizes in cold vs warm env (Fig. 31.8)
Plant systems- roots, stems, and leaves (Figs. 27.16, 27.21)
Special morphologies- mycorrhizae, root hairs, cladophylls, spines, needles…
Trade-offs
Plant cell and tissue types
Xylem and Phloem
Apical and Meristem
Growth of roots and shoots (Figs. 27.8, 27.22)
Modular growth, cell division, elongation, maturation
Placement of new cells vs meristem
Ch. 29- Plant Transport/Circulation/Transpiration (621-623, Figs 29.20-29.24)
Cohesion/Adhesion/Transpiration Mechanism for water movement (pulling)
Hydrogen bonds, diffusion, osmosis, turgor pressure, stomata, guard cells,
Transpiration is necessary, but why is it carefully regulated?
Transpiration-Photosynthesis Trade-off
Water balance/homeostasis
Guard cells- sensitivity to turgor pressure, CO2 levels, blue sunlight
Ch 36- Animal Circulation (751-758)
Gastrovascular cavity (Fig, 35.2)
Which organisms have this structure for gas exchange?
What are the limitations of this system? How do these organisms compensate?
Open circulatory system (Fig. 36.1)
Which organisms have this sort of a system?
What are the limitations? How do these organisms compensate?
Closed circulatory system (Figs. 36.1 and 36.2
Which organisms have this sort of a system? What sorts of variations exist?
2 vs 3 vs 4 chambered hearts (Figs. 36.2, 37.2, and 37.3)
What sorts of animals have these systems?
What are the limitations of each system? How do these organisms compensate?
Cutaneous breathing in amphibians
Partial ventricular septum in reptiles
Blood (Fig. 36.4)
composition & function of plasma, clotting, buffer,…
RBCs- pluripotent stem cells, biconcave disk, structure and function
How does RBC mature? How are its traits functional?
Problems: 1, 2, 4, 5, 8, 9; Conceptual 2