In a forward-biased pn junction show that the ratio of the current component due to hole injection across the junction to the component due to electron injection is given by Evaluate this ratio for the case , , m, m, Dp = , and , and hence find and for the case in which the pn junction is conducting a forward current I = 1 mA.
1) a. Match the following groups with its description: Metazoa mouth develops first Deuterostomes true tissues Bilateria multicellularity/tissues Protostomes bilateral symmetry, triploblastic Eumetazoa anus develops first, then mouth b. Organize the above developments chronologically through evolutionary time by placing them on the proper number on the tree: Choanoflagella tes 1 (1) 2 5 3 5 Lophotrochozoa 4 5 Ecdysozoa c. Place the phylum from the big 9 on the tree, using the following hints if needed (because it’s sorta outrageous what they expect us to memorize)… Sponges (have a lot of POREs) are the most basic. Although Platyhelminthes, Annelida, and Nematoda are all “worms”, Nematoda are more closely related to Arthropoda, while Platyhelminthes and Annelida are more closely related to the phylum of animals with a soft body and calcium carbonate shell. We humans (think about our notochord) develop an anus before our mouth. In lab, we studied Cnidaria in the same lesson as Porifera. Echinodermata are deuterostomes. 2. With what group on the above tree did a coelom originate (Hint: diploblasts cannot have a coelom) _______________________ 3. Which of the following is NOT a characteristic of all animals a. multicellularity b. move at some stage in life c. specialized cells to organize movements d. ingestive heterotrophs e. all of the above are characteristics of all animals 4. What are the 3 major clades of Bilateria a. Deuterostomia, Lophotrochozoa, Ecdysozoa b. Echinoderms, Chordata, Protostomia c. Nematoda, Arthropoda, Deuterostomia d. Chordata, Arthropoda, Platyhelminthes 5. In psuedocoelomate body plans, the fluid filled cavity is… a. in between the endoderm and mesoderm b. completely enclosed by the mesoderm c. not present d. completely enclosed by the endoderm 6. Crustacea are included in what phyla a. Mollusca b. Insecta c. Arthropoda d. Annelida 7. Gastropods, bivalves, and cephalopods are subcategories in… a. Nematoda b. Annelida c. Echinoderms d. Mollusca 8. True or false: All chordates have a postanal tail 9. True or false: All chordates have a vertebra. 10. GNAthostomes GNAw with their jAW, which arose from which structure a. postanal tail b. notochord c. pharyngeal slits d. dorsal hollow nerve cord 11. OSteichthyes all have an OSsified bony endoskeleton, which developed into (rayed or lobed) fins in Actinopterygii 12. The next innovation of some lobefins was… a. 4 limbs with digits b. the amniotic egg c. hair d. improved gills 13. Without looking back on the previous questions at first (then refer to them if you need help), put the following innovations of chordate evolution in order of groups growing smaller and more specific: Tetrapods, osteichthyes, gnathostomes, lobefins, vertebrates, amniotes Chordates> __________>__________>__________>___________>___________>__________ 14. The main innovation of amniotes provides for… a. protection of eggs from predators b. reproduction not dependent on water c. faster movement on land d. more development to occur while in the egg 15. True or false: Amniotes include reptiles, amphibians, and mammals. 16. Circle which of the following are characteristics of ALL mammals malleus, incus, stapes, dentary, vibrissae, milk glands, whiskers, homeothermy 17. Place the following in the table (some belong in two columns): the environment supplies the organism’s heat body temperature varies conformers regulators negative feedback system metabolism produces the organism’s heat body temperature stays constant requires less energy compared to opposite insulation (mainly in…) behavioral heat absorption mainly used (heterothermic animals use both homeothermic and poikilothermic methods. To which belongs…) aestivation hibernation torpor heterothermy Homeotherm Poikilotherm Endotherm Ectotherm 18. What is the benefit of segmentation a. The organism can move more freely. b. Tissues can specialize. c. It allows for a coelom. d. all of the above 19. During what era did nearly all animal diversity arise a. Ediacaran Origin b. Metazoan Origin c. Ediacaran Exposition d. Cambrian Explosion 20. What is ecdysis a. the process of forming an embryo b. molting c. the growth of a coelom d. the beginning of deuterostome development 21. If a larger animal tends to have a lower metabolic rate, and a larger animal tends to live longer, then… a. an animal with a higher metabolic rate tends to live longer b. an animal with a lower metabolic rate tends to live longer c. a smaller animal tends to have a higher metabolic rate d. b and c e. a and c 22. Adaptations to deal with the smaller ratio of surface area to volume as body size increases include _____________, _______________, and _______________. (ex: shape of Platyhelminthes, intestinal lining, capillaries in lungs) 23. Convection is a mechanism of heat exchange which involves… a. direct contact between a solid and a gas or liquid b. direct contact between solids c. no direct contact, principally a relationship with the sun d. loosing water 24. Label the path of heat with arrows to depict countercurrent exchange, an dVein) label the coldest area and the hottest area: (Artery) 25. What is the limiting factor for insect size in recent time 26. Hox genes are in charge of… a. segmentation b. ecdysis c. protostome development d. growth of newborn 27. Which of the following is not a trend in evolution a. upright limb posture b. nocturnal habits c. smaller muscles d. larger brains 28. Compared to carnivores, omnivores have a (smaller or larger) caeca and herbivores have a larger (caeca and/or stomach). 29. Basically, every animal is a dermal _______ containing an inner, digestive ______ (same word). 30. Almost done! Fill out the table as best possible by choosing from the options for each column: Phylum Habitat (marine, Mobility (mobile or Dietary Strategy freshwater, terrestrial) sessile) (filter feeding or predatory) Platyhelminthes Mollusca Annelida Nematoda Arthropoda Porifera Cnidaria Echinodermata Chordata Answer Key: 1. a/b: (1)Metazoa (multicellularity/tissues), (2)Eumetazoa (true tissues), (3)Bilateria (bilateral symmetry, triploblastic), (4)Protostomes (mouth develops first), (5)Deuterostomes (anus develops first, then mouth) c: from top going down Porifera, Cnidaria, Chordata/Echinodermata, Platyhelminthes/Annelida/Mollusca, Nematoda/Antherpoda 2. Bilateria 3. E 4. A 5. A 6. C 7. D 8. True 9. False 10. C 11. Rayed 12. A 13. Vertebrates, gnathostomes, osteichthyes, lobefins, tetrapods, amniotes 14. B 15. True 16. Malleus, incus, stapes, dentary, milk glands, (hair in general, not all specifically vibrissae or whiskers) 17. Homeotherm Poikilotherm Endotherm Ectotherm body temperature body temperature metabolism the environment stays constant varies produces organism’s supplies the regulators conformers heat organism’s heat negative feedback aestivation insulation requires less energy system hibernation heterothermy compared to torpor (includes aestivation, endotherm hibernation, torpor) behavioral heat absorption mainly used 18. B 19. D 20. B 21. D 22. Flattening, folding, branching 23. A 24. Arrows should be going from artery into vein so that blood returning to body takes the heat back to the core and heat does not travel all the way to the extremity. Therefore the coldest part should be the bottom and the hottest part should be the core/top. 25. Lesser concentration of oxygen in the air; tracheae and tracheoles work simply by diffusion and the lesser concentration does not supply efficiently enough. 26. A 27. C 28. Larger; caeca AND stomach 29. Tube 30.