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The Boston barberry is an imaginary plant with a diploid chromosome number of 4, and Boston barberry cells are easily grown in suspended cell cultures. 3H-thymidine was added to the culture medium in... In Drosophila, the genes st (scarlet eyes), ss (spineless bristles), and e (ebony body) are located on chromosome 3, with map positions as indicated: st....... ss ........ e 44.......58.......70 Each... What change in blood vessel diameter would raise blood pressure? Classify each of the following descriptions as either a proximate or an ultimate cause of behavior. For all proximate causes, speculate about a possible ultimate cause of the behavior. a. A surge of... A liquid of 27 wt% acetone and 73 wt% water is to be separated at 25C into a raffinate and extract by multistage, countercurrent liquid liquid extraction with a solvent of pure 1,1,2-trichloroethane.... Liquids A and B, which have nearly identical boiling points, are to be separated by liquidliquid extraction with solvent C. The following data represent the phase equilibrium at 95 C. Determine the... In Examples 15.13 and 15.18, benzene is adsorbed from air at 70 F in a 6-ft-high bed of silica gel and then stripped with air at 145F. If the bed height is changed to 30 ft, the following data are... Write the overall reaction of oxygen-generating photosynthesis. Explain the following statement: the O 2 generated by photosynthesis is simply a by-product of the pathway's generation of... Microinjection of an antibody known as EAGE, which reacts with the "hinge" region of the subunit of COPI, causes accumulation of Golgi enzymes in transport vesicles and inhibits anterograde... Where are stem cells located in plants? Where are stem cells located in adult animals? How does the concept of stem cell differ between animal and plant systems? Cytokinesis, the process of cytoplasmic division, occurs shortly after the separated sister chromatids have neared the opposite spindle pules. How is the plane of cytokinesis determined? What are the... In the 1960s, the drug thalidomide was prescribed to pregnant women to treat morning sickness. However, thalidomide caused severe limb defects in the children of some women who took the drug, and its... According to health experts, saturated fatty acids, which come from animal fats, are a major factor contributing to coronary heart disease. What distinguishes a saturated fatty acid from an... Mobile DNA elements that can move or transpose to a new site directly as DNA are called DNA transposons. Describe the mechanism by which a bacterial DNA transposon, called an insertion sequence, can... Compare/contrast bacterial and eukaryotic gene expression mechanisms. Hoechst 33258 is a chemical dye that binds specifically to DNA in live cells, and when excited by UV light, it fluoresces in the visible spectrum. Name and describe one specific method, employing... The membrane potential in animal cells, but not in plants, depends largely on resting K + channels. How do these channels contribute to the resting potential? Why are these channels considered to be... If you were planning a trip to one of the countries listed in number 5, would you rather be told the death rate or the number of cases and deaths in each country? Explain. Compare the structure of WNV to that of HIV. What inferences can you draw from these data about how avian flu is transmitted to humans? Explain each one, referring to the data you used in developing that inference. What molecule does the H stand for in the name of both viruses, where is the H molecule located on the virus, and what role does the H molecule play in the life cycle of the virus? While searching for images, you find a drawing of an early swamp with a dragonfly. The caption says the dragonfly has a wingspan of 2 feet. Use 2 feet as the scale value. The size of the dragonfly... What other factors might enter into a growers decision about whether to plant Bt corn? Which substance worked best? What does this tell you about the composition of wallpaper paste? Grass forage and hay consist largely of structural carbohydrates in the form of fiber, primarily cellulose. The fiber provides the raw material necessary for the growth and maintenance of microbial... Why was it important for a systematist to identify the known cetacean species from which DNA was extracted and sequenced? Extending this investigation: Visit one of the many interactive maps on avian influenza. Two particularly good ones are offered by the British Broadcasting group in the United Kingdom:... Which cetacean does the unknown sample most closely match? Phylogenetic trees are hypotheses that show a pattern of evolutionary relationships, based on analyses of multiple characters, for multiple taxa. A phylogenetic tree implies a chronological sequence... Divergence of cetacean species occurred within the last 50 to 65 million years (OLeary and Geisler, 1999). Explain the difference between the use of a fragment of hypervariable mitochondrial DNA as a... An attorney defending a whale meat supplier accused of improperly labeling meat would most likely claim that the inferences drawn from the prosecutions evidence were questionable. Provide a potential... Which of the trees based on molecular sequence data shown in Figure 4.10 supports hypothesis A in tree B? Explain. List three characters that you could observe in living whales that white-tailed deer or other even-toed ungulates do not seem to share. List four animal phyla that you would expect to find living in the aquatic environments of the Carboniferous including swamps and oceans. At the first meeting, the artists from Wall Works gave the biology students a list of organisms from their image files. Please evaluate whether or not the organisms listed in the following table... How long ago was the Carboniferous? List five other terrestrial organisms (not listed elsewhere in this case) that likely lived during the Carboniferous. Include organisms from at least three kingdoms. You may use common names. Could there be a food chain without herbivores and carnivores? What is an indicator species? How are indicator species used to assess pollution levels in the environment? For each of the following characteristics, indicate whether the trait is common to Phylum Arthropoda or specific to certain classes of arthropods: wings, chewing mouthparts, jointed appendages,... Molecular data can also be used to examine relationships between organisms, but the inaccessibility of comparative DNA samples for extinct taxa limits the usefulness of these data. Evidence for... In a few sentences, what were Mendels key ideas about inheritance? The following pedigree shows the inheritance of a recessive trait. Unless there is evidence to the contrary, assume that the individuals who have married into the family do not carry the recessive... Which of the following pairs of DNA sequences could qualify as target site duplications at the point of an IS50 insertion? Explain. (a) 5-AATTCGCGT-3 and 5-AATTCGCGT-3 (b) 5-AATTCGCGT-3 and... A nutritionally defective E. coli strain grows only on a medium containing thymine, whereas another nutritionally defective strain grows only on a medium containing leucine. When these two strains... A Drosophila geneticist crossed females homozygous for three X-linked mutations (y, yellow body; B, bar eye shape; v, vermilion eye color) to wild-type males. The F 1 females, which had gray bodies... Use the Internet to research cosmetic surgery. Write a paragraph explaining how a plastic surgeon might manipulate each of the four main tissue types. Distinguish between the following. a. Organs and organ systems b. Simple squamous and stratified squamous epithelial tissue c. Loose and dense connective tissue d. Skeletal and cardiac muscle tissue... Describe the events that occur during one cardiac cycle. What is the function of heart valves? Why might a person with a leaky heart valve feel short of breath? Eight independently isolated mutants of E. coli, all of which are unable to grow in the absence of histidine (his), were examined in all possible cis and trans heterozygotes (partial diploids). All... What are the two main functions of food in an animals body? On a per-kilogram basis, why does a small mammal such as a shrew require so much more energy than does an elephant or other large mammal? A solution at 107 C contains 50 mol% water (W) and 50 mol% formic acid (F). Using (2-72) with vapor pressure data and the van Laar equation with AWF = -0.2935 and AFW = 0.2757: (a) Compute the... A test leaf filter is used to determine the filtration rate for an unclarified broth from a fermentor. At a pressure drop of 50 kPa, 150 mL of filtrate are collected in 30 minutes. If the resistance... A 6-inch demister pad is to be used to separate liquid entrainment from a gas in a horizontal flash drum. Calculate the demister diameter using the following data: Vapor flow rate = 465 cfm at 110F... For a solid, spherical particle of 0.8 mm in diameter and a density of 2,600 kg/m 3 that is immersed in a fluid of density 1,200 kg/ m 3 and a viscosity of 1.0 cP, calculate (a) The unhindered... Referring to figure 30.4, speculate about which blood type is considered the universal donor and which is called the universal recipient. Explain your answer. Figure 30.4 Donor blood group AB A A... Fifty wt% methylcyclohexane (MCH) in n-heptane is fed to a countercurrent, stage-type extractor at 25 C. Aniline is the solvent and reflux is used at both ends of the column. An extract containing... CaCO 3 precipitate can be produced by reaction of an aqueous solution of Na 2 CO 3 and CaO, the byproduct being NaOH. Following decantation, slurry leaving the precipitation tank is 5 wt% CaCO 3 ,... A slurry is passed through a filter cloth 0.02 m 2 in area at a constant rate, with 4 x 10 5 m 3 /s of filtrate being collected. After 100 s, the pressure is 4 x 10 4 N/m 2 ; after 500 s, it is 1.2 x...
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