ECOL 182R 1st Edition Exam 2 Study Guide Lectures 6 10 Lecture 6 Historically life was divided into two groups What were these two groups Bacteria everything else Or formally expressed prokaryotes eukaryotes Who challenged the fact that life was only divided into two groups What did he propose instead Carl Woese He proposed the term Archaebacteria for a group of prokaryotes living in strange environments with distinct rRNAs True or false Bacteria and Archaea both have histones False Archaea and Eukaryotes have histones What is microbiology The study of microbes or microscopic organisms What are Koch s Postulates use to confirm A causative link between a specific infectious disease and a specific microbe What are bacteria or Archaea that live in high salt high temperature or high pressure habitats called Extremophiles True or false One reason that bacteria are hard to work with and be characterized is because they are hard to culture so they are overlooked True What are cyanobacteria and what were they responsible for They are a lineage of photosynthetic bacteria and were the first organisms to perform oxygenic photosynthesis They were responsible for changing the Earth s atmosphere to one with a high concentration of oxygen What do carbon compounds serve as for all organisms Serve as building blocks for synthesis of cellular components What are the 6 major groups of bacteria Firmicutes Spirochaetes Actinobacteria Cyanobacteria Chlamydiales Proteobacteria True or false Archaea live in every habitat True Even extreme ones Lecture 7 What are deep branching eukaryotes Those that diverged shortly after the split of the major domains in life They re protists What is the causal agent of Malaria What do control strategies target Plasmodium Mosquitos What are four characteristics of Red Tides 1 Massive blooms of dinoflagellates 2 High concentration of red pigments the ocean can turn red 3 Dinoflagellates produce a toxin to defend against copepod predators 4 Paralytic shellfish poisoning What is the major importance of protists By fixing carbon they generate food and energy upon which the rest of the food chain depends on What are the three ways that protists move 1 Amoeboid motion via pseudopodia Crawling 2 Swimming via flagella whip like structures 3 Swimming via cilia which are basically ores True or false Protists only have an extensive diploid life cycle phase False They can have both extensive haploid and diploid cycle phases Lecture 8 What are two characteristics of Diplomonadida Each cell has two nuclei each associated with four flagella It s a very deep branching eukaryote Which protist family has a silicon rich shell is photosynthetic and has a big fossil record Diatoms Which protist family is the only multicellular one and includes most kelps Brown algae What are three characteristics of fungi 1 Terrestrial ecosystems 2 Feed by absorption 3 Unusual life cycles Name four diseases that fungi can cause to humans Valley fever athlete s foot vaginitis and ringworm Fungi have a very high surface are to volume ratio How does this affect absorption It makes absorption extremely efficient but also makes fungi prone to drying out What are the two ways fertilization happens in fungal life cycles Fusion of cells and fusion of nuclei from the fused cells Name and describe the four reproductive structures used to classify fungi Chytridiomycota only fungi with mobile cells Zygomycota have zygosporangium yoke structure Basidiomycota basidia form at ends of hyphae Ascomycota tips of hyphae produce saclike cells called asci that generate spores Lecture 9 What is the difference in chromosomes between meiosis and mitosis In meiosis chromosome number is halved Mitosis preserves the chromosome number What do sporophytes make What do gametophytes make Spores Gametes True or false Gametophytes and sporophytes are both diploid False Both are haploid What are 3 characteristics of nonvascular plants Have protected embryos They re small plants compared to present day shrubs trees Lack tracheids Have stomata What are stomata Pores that open and close that regulate CO2 uptake What do tracheids in vascular plants help with More efficient water movement and support for tall plants Describe angiosperms Highly diverse and make up 80 of life on earth They have unique traits flowers fruits Virtually all plant material that we eat comes from angiosperms Pollen tubes grow down to deliver sperm to egg True or false Animal pollination is usually better than wind pollination True Lecture 10 Define symbiosis Intimate association between unrelated organisms not necessarily beneficial How much bacteria can be cultured Less than 1 What does polymerase chain reaction do Why is it valuable Makes lots of DNA from very small amounts Valuable because then you can visualize it and then sequence it Why is DNA sequencing valuable You can see how often a bacterium is present Why is the mammalian gut flora valuable You can separate the difference of two bacteria and see the role of each bacterium What did the Human Microbiome Project do Characterized all bacteria associated with humans In insects how the bacteria in their cells transmitted to other insects It s transmitted from mother to offspring in egg cytoplasm It isn t contagious What does bacteria in guts influence Muscle contractions the vascular network association with microvilli and the intestine s capacity to absorb nutrients What percent of feces is bacteria 50