We see a great deal of variation in reproductive strategies in the animal kingdom. Evaluate the basic strategies and trends in egg fertilization and protection in sexually reproducing animals
What will be an ideal response?
The more primitive animals simply release sperm and egg cells into the environment, leaving it largely to chance that the egg cells and sperm will get together. In more complex animals, there is a trend toward producing fewer gametes (particularly eggs), and there are more reliable methods for getting sperm and egg together. Internal fertilization seen in higher animals is one method that accomplishes this goal. Also, there is a trend toward greater protection of eggs by protective behaviors and even by housing the fertilized egg and embryo inside the mother (viviparous reproduction).
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An individual can receive injections of an antiserum or purified antibodies derived from an immune individual
Indicate whether the statement is true or false.
How did the control group differ from the
experimental group in the butterfly experiment? a. They were different species. b. Their native habitat area of the forest differed. c. They tasted worse. d. They were white-patterned. e. They preferred different flower species.
A lytic virus has infected a patient. Which of the following would best describe what is happening inside the patient?
A) The virus is causing the death of the infected cells in the patient. B) The virus is not killing any cells in the host. C) The virus is incorporating its nucleic acid with that of the patient's cells. D) The virus is slowly killing the patient's cells. E) The virus is infecting cells and then releasing only small amounts of virus.
Which sequence of events is correct for a specific immune response?
A. lymphocyte development, presentation of antigens, antibody production, challenge of B-cells B. antibody production, lymphocyte production, B-cell challenge, presentation of antigens C. lymphocyte development, presentation of antigens, B-cell challenge, antibody production D. presentation of antigens, B-cell challenge, antibody production, lymphocyte development E. lymphocyte development, challenge of B-cells, antibody production, presentation of antigens