Friday, 6/1/2007 (Lecture 1): In today's lecture session, the administrative policies and organization of the BIO 103 course for Summer session I, 2007, were presented to the class. As part of the PowerPoint presentation delivered to the class, a website address for the electronic version of the course syllabus was provided to the students. The day's lecture was directed at identifying a few of the major characteristics (such as "chemical uniqueness" and cellular composition) of all living things.
A FEW WORDS ABOUT VIEWING THE PRESENTATIONS AND VIDEOS: The following lecture presentations are not actual PowerPoint files but are instead PowerPoint files that have been converted (using a program called Impatica for PowerPoint) to Java applets embedded in HTML files. The end result is that when you click on the links below you should be able to view the class presentations in your web browser (as long as your browser is Java-enabled). The pop-up blockers on web browsers sometimes are set to block any Java function, so you may need to turn off the pop-up blocking function of your browser to view the presentation. Conversion of these files using Impatica means that you are able to view these shows without having to add any plug-ins or any additional software (including PowerPoint) on to your computer; you can view them on any computer as long as you have web access and an internet browser. The presentation files are optimized for use with Internet Explorer, but they generally function well enough with Mozilla Firefox, too. The videos are the actual video files that are viewed in class and are typically in WMV file format. the video files are sometimes large, and it might take a while to view the files using your computer, depending on your machine and your Internet connection speed. I strongly urge you to access the videos using a computer with broadband access to the Internet. Dial-up connections really, really, REALLY are too slow to realistically allow you to view these video files in most cases.
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Monday, 6/4/2007 (Lecture 2): Much of the first part of today's lecture addressed the roles played by proteins in cells, especially eukaryotic cells such as the ones that are found in members of the kingdom Animalia. Special attention was given to the repair proteins (heat-shock proteins, chaperones, and ubiquitins), which assist other cellular proteins in maintaining proper shape, repairing/degrading damaged proteins, etc. A slightly expanded description of the differences between protein synthesis in prokaryotes and eukaryotes, taking into account RNA splicing in eukaryotes, was provided. Cellular structures (ribosomes, endoplasmic reticulum, and Golgi apparatus) that are important in translation and post-translational modifications of proteins were described. The traditional model of a cell membrane was presented to the class, along with mention of how this "fluid mosaic" model is evolving. A discussion of how eukaryotic cells generate energy in the form of ATP followed. Aerobic vs. anaerobic processes were identified. The role of oxygen in electron transport (= oxidative phosphorylation) was described; chemiosmosis was defined. The structure of the mitochondrion was briefly discussed, and the evidence for a prokaryotic origin for mitochondria was presented. Apoptosis was defined.
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Tuesday, 6/5/2007 (Lecture 3): Discussion of the various ways that biologists categorize all of the known living things was conducted in lecture today, with consideration given to the 5, 6, and 3 kingdom taxonomic arrangements. The use of the ribosome by molecular biologists in recognizing Archaea, Eubacteria, and Eukaryota was noted. Most of the lecture period was spent describing unicellular eukaryotes in the kingdom Protista (in a 5-kingdom classification system). The emphasis of locomotion in classification of Protista was mentioned. African trypanosomiasis and leishmaniasis (both cutaneous and visceral forms) were provided as examples of important human illnesses caused by protistans. Malaria was identified as another important protistan-caused illness in humans. After some final thoughts about unicellular eukaryotes, we examined some of the similarities and differences that exist among the three (in a 5-kingdom system of biological classification) multicellular kingdoms, Animalia, Plantae, and Fungi. Some of the connections between Fungi and Animalia were specifically noted. Our attention then turned toward the specific characteristics of members of the kingdom Animalia. The four basic tissues found in animals (epithelium, connective tissue, muscle, and nerve) were identified before a more detailed discussion of epithelium ensued. Connective tissue was described superficially before we left the lecture.
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Wednesday, 6/6/2007 (Lecture 4): Discussion of the four basic tissues found in animals continued today, as we examined connective tissues (in more detail), muscle, and nerve. The main structural features of each of these tissues were identified. The features of some special connective tissues were mentioned. The multinucleate organization of skeletal muscle cells was noted during our look at muscle. After we completed our list of some of the basic characteristics of members of the kingdom Animalia, some aspects of the biology of members of the phylum Porifera were presented. Spongin and spicules were described. The interest of some research groups in the structure of hexactinellid sponge spicules, for clues about better ways to manufacture better fiber optics, was reported.
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Thursday, 6/7/2007 (Lecture 5): Our examination of the phylum Porifera continued today as we looked at the types of cells that sponges are composed of, as well as other features of typical sponge anatomy. he functions of pinacocytes, porocytes, amebocytes, and choanocytes were stated in a general way. The relationships between zooxanthellae/zoochlorellae and many sponges were noted. Some of the mechanisms used by sponges to deal with competing organisms were mentioned, and the position of sponges among the proposed agents of "bioerosion" of coral reefs was reported. Numerous images of sponges in the class Demospongiae were viewed, and a few specimens of the class Calcarea were observed. The utility of sponges in the laboratory study of cellular adhesion molecules was described. Sponge reproduction was briefly discussed, and some time was spent describing their ability to serve as seasonal/functional hermaphrodites. A few final thoughts about the poriferans were delivered, before our attention was directed toward the members of the phylum Cnidaria. Patterns of sponge development were described, and the significance of gemmules was elucidated. The three cnidarian classes (Hydrozoa, Scyphozoa, and Anthozoa) we shall study were identified. The structure of cnidocytes was discussed, including mention of the nematocyst that is discharged when physical contact is made with the cnidocil. Some time was devoted to examining the structure of the body wall of a typical representative cnidarian, a hydra. Some of the basic biology of the Hydra polyp was described. We examined the life cycle of Obelia, a well-studied colonial hydrozoan. "Alternation of generations" was described. We also peeked at the biology of various other members of the class Hydrozoa, such as the Portuguese man-o-war and hydrocorals (such as fire coral). The role of zoochlorellae/zooxanthellae in permitting hydrocorals to trap calcium carbonate (and thus be hydrocorals) was mentioned. The connection between green fluorescent protein (GFP) and Aequorea (a hydrozoan) was discussed. Transgenic animals were defined. The presentation of the biology of the class Scyphozoa began by looking at the life cycle of Aurelia, a common marine jellyfish. Lack of sexual dimorphism in medusae was noted. The box jellyfishes, sometimes placed in the class Cubozoea, were singled out for their ability to produce pain (and even death) in humans who are stung by the nematocysts of these organisms.
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Wednesday, 6/13/2007 (Lecture 6): The class Anthozoa was presented to the class today as part of our continuing discussion of the phylum Cnidaria. General features of he biology of the anemones and the corals were described. The dominance of the polyp form in both the individual (anemones) and colonial (corals) anthozoans was illustrated with many images. Attention is given to the role of symbiotic dinoflagellates (zoochlorellae/zooxanthellae) in the formation of a calcium-based skeleton by hard corals. Different forms of symbiosis (phoresy, mutualism, commensalism, parasitism) were defined for use in connection with studies of animals. The position of Porifera and Cnidaria as so-called "diploblastic" phyla was identified, setting these animals apart from all of the other phyla that we will talk about during this summer session. The basic characteristics of members of the triploblastic phylum Platyhelminthes were mentioned, before we began a more detailed examination in lecture of the class Turbellaria as representative flatworms. The general structural organization of the turbellarians (acoelomate, body organs suspended in a spongy parenchyma) was described. The existence of several organ systems in turbellarians was noted. Osmoregulation in turbellarians was described, and the role played by the protonephridia in water balance was mentioned. The importance of turbellarians to the scientific study of wound healing/tissue regeneration was briefly reported. A quick glance at the class Trematoda was made toward the end of the lecture period, with Fasciola hepatica used as an example of a well-studied, typical trematode.
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Want to see a quiz over some of the lab material? Click here to see some images and questions that are representative of things that you might see on the laboratory practical examination.
Thursday, 6/14/2007 (Lecture 7): More on Fasciola hepatica was presented in class today, illustrating some of the general features of the biology of trematodes via the discussion of this organism. A form of "alternation of generations" as seen in the trematodes was observed in the life cycle of F. hepatica. Another trematode model, the lung flukes in the genus Paragonimus, was also described in class. The use of crustacean second intermediate hosts by this group of flukes was noted. We began to look at the trematodes in the genus Schistosoma, important for their role in causing schistosomiasis in humans in many parts of the world. Much of the lecture was spent explaining how Schistosoma mansoni and S. japonicum contribute to the formation of portal hypertension.
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Friday, 6/15/2007 (Lecture 8): Today's lecture consisted of an expanded look at the schistosomes, trematodes that are common and important parasites of humans in much of the world but which do not fit the "typical trematode" model. The role of the three most important species of human schistosomes in producing illness in people was discussed. The ability of S. haematobium to cause hematuria was mentioned. We considered the biology of the class Cestoda, the tapeworms, in lecture today. The basic cestode life cycle (strobilar stage, metacestode, egg) was introduced and vividly illustrated using examples such as Hymenolepis diminuta (a rat tapeworm that can also infect people) and Dipylidium caninum, a common tapeworm of dogs and cats. The beef tapeworm, Taenia saginata, was identified and additional information about cestodes was provided in class about the biology of Taenia solium, the pork tapeworm. The role of Taenia solium in causing neurocysticercosis in humans was discussed.
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Tuesday, 6/19/2007 (Lecture 9): The phylum Nematoda was introduced in lecture today, with a quick first look at an example of what a parasitic nematode (the giant kidneyworm) can do in a susceptible canine host. The general structure of nematodes was described, with emphasis placed on the three layers of the body wall and internal organs suspended in a fluid-filled pseudocoelom. The basic nematode life cycle was outlined. Comments were made about sexual dimorphism in nematodes. General reproductive patterns of roundworms were described; the use of parthenogenesis in some nematodes was mentioned. Caenorhabditis elegans was identified as an important experimental animal, the first organism to have its genome sequenced. We examined the life cycle of a typical parasitic ascarid nematode (Parascaris equorum) as part of our study of nematode biology. Mention was made of the fact that similar ascarids live in the small intestines of pigs and humans, and that the problems these worms cause in pigs and humans are similar, too, to the problems caused by P. equorum in equids. The biology of lymphatic-dwelling filarioid nematodes, which use mosquitoes as intermediate hosts was described, illustrating another pattern followed by some parasitic nematodes.
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Wednesday, 6/20/2007 (Lecture 10): The segmented worms, the phylum Annelida, were introduced in lecture today. Oligochaeta, Polychaeta, and Hirudinea were introduced as the annelid classes that we will recognize during the semester. General characteristics of the Annelida were focused on, such as the phenomenon of metamerism observed in members of this phylum. Advanced cephalization was also mentioned as a feature of the annelids. The presence of a true coelom was reported, and the components of a circulatory system of the type found in an annelid were noted. Issues related to the elimination of nitrogenous wastes from the bodies of terrestrial annelids were mentioned. The roles for the chitinous chaeta (=setae) found in the annelids were mentioned. Video of a live polychaete was viewed. Advanced cephalization as found in the polychaetes was described, and some of the connections between the polychaetes and the arthropods were mentioned. Trochophore larvae were described.
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Thursday, 6/21/2007 (Lecture 12): The structure of a typical gill was delineated, and the role of the gills in filter-feeding in some polychaetes (such as tube worms) was noted. The biology of leeches (class Hirudinea) was generally described, and information about the medicinal use of leeches in contemporary human/veterinary medicine was presented. Some leech video was followed by an introduction to the arthropods. The subphylum Chelicerata dominated today's lecture presentation. Much of the lecture focused on the horseshoe crab. The open circulatory system of arthropods was presented. The general features of chelicerates were discussed. The risks of molting for terrestrial arthropods was described. Sexual dimorphism among the spiders and the function of spermatophores in spider reproduction both were also discussed. Ways that nonspecifically-feeding predators handle contact with members of their own species were listed.
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Friday, 6/22/2007 (Lecture 13): Other arachnids were briefly mentioned, before a description of the life cycle of a typical hard tick was provided to the class. Some information about a group of mammalian mites, members of the genus Demodex was relayed to the class. Subsequently, we moved on in our course discussion to the subphylum Uniramia. The general characteristics of the subphylum were listed in class. The class Insecta was the recipient of most of the lecture's attention, since these make up the largest group of uniranians. The last part of the lecture was devoted to study of the members of the arthropod subphylum Crustacea. Basic structural features of crustaceans were identified. The nauplius larva of crustaceans was described. Specialization of appendages in crustaceans was mentioned. Although crustaceans were said to be primarily aquatic organisms, the terrestrial isopods were described. Some of the small freshwater crustaceans were shown in the lecture presentation. Bivalve crustaceans known as ostracods were discussed as class dre.w to a close
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Monday, 6/25/2007 (Lecture 14): With the arthropods behind us, study of the phylum Mollusca now begins in BIO 103 lecture. After identifying the general characteristics of the members of the phylum, discussion of the Mollusca focused on the biology of the members of the class Bivalvia. Filter feeding and its consequences for humans who eat raw/undercooked bivalves was described. We briefly looked at the effects of the introduced zebra mussel (a bivalve) on North American freshwater ecosystems. Our attention soon turned, however, to the biology of the cephalopods. The structural features of the cephalopod eye were identified, and the cephalopod eye was compared to the human eye. The neurological control of chromatophores was described.