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Mr. Silva teaches sixth-grade language arts. At the beginning of every school year, he spends the first five days of schools setting up rules and procedures. Before school begins, Mr. Silva prepares a list of rules and procedures he wants the students to learn and follow. The first day of class he passes out the list and gives students time to read it. He goes over each rule and procedure with the students and asks for their comments about the fairness of each. May students do comment, and when Mr. Silva feels the comments are justified, he changes or modifies the rule or procedure. When he and the students are satisfied, he begins practicing the procedures with the students. When the students demonstrate knowledge of the classroom procedures, Mr. Silva begins to teach course content. Why does Mr. Silva involve the students in the creation of classroom rules and procedures?

There are four major groups of extant, or living, fishes: the jawless fish, the cartilaginous fishes, and the bony fishes.  Although these 3 groups differ considerably, they do share certain features in common. Which of the following features is NOT found in all 3 major groups of extant fishes?

What group of chondrichthyans are MOST LIKELY to exhibit a form of locomotion known as punting?

The graph below is from a study on male Atlantic sharpnose sharks. At what size does the male Atlantic sharpnose shark become sexually mature?   

It has been suggested that the decline in sandbar sharks that occurred along the mid-Atlantic states in the last 1980s to early 1990s resulted in a significant increase in populations of the chain catshark.   As you may remember from class, Grubbs proposed that there are several criteria or diagnostics that must be considered when evaluating whether a hypothesized trophic cascade has truly occurred.  They are shown in the picture below, along with temperature preference data for these two species and other elasmobranchs. Based on these data, which of the listed criteria do NOT support this hypothesized trophic cascade?     

So…white sharks are cowards… Which of the following is MOST likely to be a possible PROXIMATE cause for this cowardly behavior?

Which of the following groups of fishes are widely believed to have given rise to the Chondrichthyes, based on the presence of “transitional fossils” that appear to exhibit traits that are intermediate to this group and the ancient chondrichthyans.

Which of the following was the first major intended commercial use for sharks in the U.S. in the early 1900s?

The picture below shows a stable isotope biplot for stable isotopes of carbon and nitrogen in species collected from a South Carolina estuary. The goal of this study was to examine food web structure in this estuary. As you can see, there were several elasmobranchs included in this study. Based on these data, which of the species listed below is the BEST example of a mesopredator?   

What is the nature of the relationship between temperature and metabolic rate in the chondrichthyans?