1.What is the lecture mainly about?
A. Methods of analyzing toxic proteins in snake venom
B. Insights about snake evolution provided by venom analysis
C. How snake venom differs from lizard venom
D. Why colubrids are considered nonvenomous snakes
2.Why does the professor review information about the classification of snakes that students probably learned in previous courses?
A. To determine whether the students have enrolled in the appropriate course
B. To stress the usefulness of the classification system for students
C. To present assumptions that have recently been challenged
D. To give an example of a method that she will explain in greater detail
3.According to the professor, what is a major weakness of the classification system that is based on animals’ physical characteristics?
A. It can show the relationships only among a small number of animal species.
B. It requires technology that is not widely available.
C. It cannot account for characteristics that first appeared in the recent geologic past.
D. It cannot determine whether similar characteristics developed in similar ways.
4.According to the professor, in what way do colubrid snakes differ from other venomous snakes?
A. Colubrids did not evolve from lizards.
B. Colubrids do not use venom to catch their prey.
C. The front teeth of colubrids are much larger than those of other venomous snakes.
D. Colubrids produce a much stronger type of venom than other venomous snakes do.
5.Why does the professor mention the brown tree snake?
A. To support a hypothesis about the evolution of constrictor snakes
B. To support a hypothesis that venomous snakes evolved from constrictor snakes
C. To give an example of a snake species that was never venomous
D. To give an example of a type of snake that can change its color
6.What is the professor’s attitude toward the result from medical research on snake venom proteins?
A. She is enthusiastic about the drugs that have been tested to date.
B. She is concerned about the side effects of drugs created from snake venom proteins.
C. She doubts that the DNA database will be useful in developing new drugs.
D. She thinks it is too early to tell how successful the research will be.