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The evolutionary pathways of several species are represented in the diagram below.
Which species was best adapted for survival in changing environmental conditions?*
The diagram below represents the bone arrangements in the front limbs of three different species of mammals.
The similarities and differences in these limbs suggest that all three species developed from the same ancestor, but*
In 1970, a deadly disease spread through corn crops in the United States. Scientists discovered that 80 percent of the corn contained the gene that made the plants more likely to be infected with the disease. This problem might have been avoided if the cornfields across the country had had more*
One possible explanation for the fact that some simple, one-celled organisms did not evolve into complex, multicellular organisms is that*
Potatoes were the main crop in Ireland in the 1800s. Almost the entire population of Ireland was dependent on a single variety of potato, the “lumper.” These potatoes were reproduced by a method of asexual reproduction known as vegetative propagation. In the middle of the 1800s, a disease caused by a fungus killed almost the entire lumper crop within two years. As a result, millions of people in Ireland died of starvation. The most likely reason the potato disease was able to destroy the potato crop in such a short time is that the*
Survival of at least a few members of a population after a major environmental change is most dependent on*
Base your answers to questions 7 on the information below and on your knowledge of biology.
The Galapagos pink land iguana, Conolophus marthae (C. marthae), is native to only one of the Galapagos Islands. Its entire range is currently limited to Wolf Volcano on Isabella Island. The iguana was first discovered on this island in 1986. Genetic studies of the animal began sometime later, and it was identified as a species separate from other iguana populations on the Galapagos in 2009. Its population might have been as high as 100 in 1986, but now there might be as few as 10 of the animals left alive.
Other evidence indicates that this species could have diverged from another line of iguanas about 5.7 million years ago. After that, the other line of iguanas diverged into two other species, C. pallidus and C. subcristatus.
In the future, the current population of about ten pink land iguanas will probably*
Each row in the chart below represents a different population of the same species of insect. Which row shows the population with the greatest chance of survival in a changing environment?
A farmer wanted to rid his apple trees of a particular leaf-eating insect. He sprayed his trees with an insecticide that killed 98% of the insects. The survival of 2% of this population of insects is most likely due to*
Base your answer to question 10-14 on the information below and on your knowledge of biology.
New varieties of organisms have resulted from human activities. These organisms have often led to problems in modern society. Two of these new varieties are listed below.
Antibiotic-resistant bacteria Pesticide-resistant insects
Select one of these varieties and discuss a problem associated with the development of this new variety of organism. In your answer, be sure to:
• identify the variety you selected
• identify one biological process by which a population of this variety may develop resistance 
• describe how this process is involved in the production of a population of resistant organisms 
• identify one problem caused by this resistance 
• state one solution to this problem 
• identify one possible negative effect of this solution 
For many years, health officials had encouraged using antibacterial hand soap. Today, many scientists recommend using hand soap with no added antibacterial substances. State one reason why using antibacterial hand soap may no longer be recommended. *
Base your answers to questions 16 on the information below and on your knowledge of biology.
EVOLUTION OF THE ELEPHANT
Today’s elephants are the result of a long process of evolution. Over millions of years, small changes were passed from one generation to the next. The first fossil elephant species were small, but over time, they increased both in size and weight. The three species alive today are the sole survivors of a once much more widespread group.
Explain why some elephant species did not survive. *
Several students were diagnosed with strep throat. They were all given the same antibiotic and took it for the time specified. Three weeks later, after finishing all their antibiotic, all the students except one no longer had strep throat. State one likely reason why the one student was still infected with strep bacteria. *
Base your answers to questions 18 on the information below and on your knowledge of biology.
Project Frozen Dumbo – Saving the Elephant Population Means Using Special Breeding
Over the last 10 years, 70 percent of Africa’s wild elephant population has been killed off. The main cause is ivory poaching, in which elephants are slaughtered for their valuable tusks. At the same time, efforts to breed captive zoo elephants have not been very successful.
Now there is some good news. At zoos in Austria and England, two baby elephants were born, using sperm from South African wild elephants. For the first time, elephant sperm gathered in the wild was frozen and given to zoos. Two female zoo elephants were artificially impregnated with the sperm and went on to deliver calves. …
Source: Saving the Elephant Population Means Using Special Breeding, Pittsburgh Post-Gazette, 8/21/14
State one reason why the use of sperm from wild elephants, rather than the use of sperm from elephants in zoos in England or Austria, would be more important to the long-term survival of elephants. *
Base your answers to questions 19 on the information below and on your knowledge of biology.
Female Shark Reproduced Without Male DNA, Scientists Say
A hammerhead shark that gave birth in a Nebraska aquarium reproduced without mating, a genetic analysis shows.
This form of asexual reproduction, called parthenogenesis, has been found in other vertebrate species, including some snakes and lizards. But this is the first time it has been documented in a shark.…
Instead, the female shark’s own genetic material combined during this process of cell division that produces an egg. A cell called the secondary oocyte, which contains half the female chromosomes and normally becomes the egg, fused with another cell called the secondary polar body, which contains the identical [amount of] genetic material….
Robert E. Hueter, director of the Center for Shark Research at the Mote Marine Laboratory in Sarasota, Fla., said the finding helped fill a gap in understanding parthenogenesis, which has been found to occur in most vertebrate lines except mammals, and until now, cartilaginous fishes like sharks….
“It’s a last-resort tactic that animals use when they absolutely can’t find another mate,” Dr. Hueter said.
Source: Henry Fountain, The New York Times, May 23, 2007
Explain why parthenogenesis could prove to be harmful to the survival of this species if it were the only method of shark reproduction. *