The northern elephant seal was hunted almost to extinction during the 18th and 19th centuries. Less than 100 seals were left to contribute to the gene pool of their future generations. Since the early 20th century, the elephant seals have been protected by law in both the U.S. and Mexico. Over 100,000 seals now inhabit the western shores of North America, all related to the small population that survived the slaughter of hunters.Scientists fear the elephant seals may be more susceptible to disease and pollution due to
A. founder effect.
B. disruptive selection.
C. heterozygous advantage.
D. bottleneck effect.
Answer: D
You might also like to view...
Which of the following are malaria vaccines currently in development?
A) synthetic peptide vaccines B) recombinant particle vaccines C) DNA vaccines D) synthetic peptide, recombinant particle and DNA vaccines
Which of the following statements is false?
a. The movement of water into a seed is known as imbibition. b. Water is attracted to hydrophilic proteins in the seed. c. The shoot system is the first part of a cotyledon to grow. d. A germinating seed starts aerobic respiration when the seed coat splits. e. Germination is completed once the primary root extends outside the seed.
________ play important roles in maintaining the blood-brain barrier.
A. nodes of Renvier B. oligodendrocytes C. microglia D. astrocytes
What would be strong evidence to suggest a protist is phototrophic?
A. Locomotion via several flagella B. A benthic lifestyle C. The presence of chloroplasts D. Silicon dioxide cell walls E. Many lysosomes