USATESTPREP Biology (Evolution)

Charles Darwin was credited for writing the biological theory of __________________. The organisms that were used for the basis of his studies were ___________________. A) evolution by natural selection, sweet peas B) inheritance by independent assortment, sweet peas C) evolution by natural selection, Galapagos finches D) inheritance by independent assortment, Galapagos finches evolution by natural selection, Galapagos finches. Darwin observed bill differences in Galapagos finches, depending on the food source on different islands and wrote the theory of evolution by natural selection.

C) evolution by natural selection, Galapagos finches

Natural selection can lead to the formation of a new species which is called A) fitness. B) mutations. C) selection. D) speciation. Speciation is the term used to describe the formation of a new species due to natural selection.

D) speciation.

How can a geological time scale BEST be reconstructed? A) comparing vestigial structures in living species B) comparing homologous structures in living species C) examining homologous structures in fossil remains D) examining the written records of scientists from past cultures examining homologous structures in fossil remains It is possible to get an idea of how things change and evolve by comparing how fossils change over time.

C) examining homologous structures in fossil remains

Biotechnology has helped produce crops that are resistant to certain pests, crops that produce high yields, and more nitrogen-efficient crops. What is a negative impact that bioengineered plants may have on the environment? A) Beneficial insects may be adversely affected. B) Plants have an increased resistance to insect pests. C) There is an increased need for inorganic fertilizers. D) Genetically engineered plants may have a longer shelf life. Beneficial insects may be adversely affected. While some insects are plant pests, many others a necessary to pollinate the flowers of plants that eventually give us fruits, vegetables, and seeds for human use. Bioengineered plants often require less water, fertilizers, pesticides, and the use of herbicides.

A) Beneficial insects may be adversely affected.

The diagram shows a type of extinct species, pterosaur, a bat, and a type of bird, a cormorant. All three organisms have wings that look and work alike, but were not evolved from a common ancestor. Which term is used to descibe body structures that look alike and serve a similar function but are not descended from a common ancestor? A) Analogous structures B) Vestigial structures C) Evolutionary features D) Homologous structures Analogous structures. Analogous structures are the result of similar needs and co-evolution of parts among organisms that are not closely related.

A) Analogous structures

The cheetah is one of the fastest animals on the planet. How would Lamarck best explain this trait? A) Cheetahs were forced to run as fast as they could to catch prey; the more they ran, the faster they became and passed this on to their offspring. B) Those cheetahs who ran fast were able to get food and survive and reproduce, passing this trait on to offspring. C) Through the survival of the fittest, slow cheetahs died. D) The environment chose fast cheetahs. Cheetahs were forced to run as fast as they could to catch prey; the more they ran, the faster they became and passed this on to their offspring. Lamarck believed in the inheritance of acquired characteristics, meaning that any behavior or trait acquired during an organism's lifetime would be passed on to offspring. Lamarck's theory is inaccurate. Darwin's theory of evolution by means of natural selection states that organisms most suited to the environment survive, reproduce, and pass these advantageous traits on to offspring. Those not well adapted die.

A) Cheetahs were forced to run as fast as they could to catch prey; the more they ran, the faster they became and passed this on to their offspring.

The cheetah is one of the fastest animals on the planet. How would Lamarck best explain this trait? A) Cheetahs were forced to run as fast as they could to catch prey; the more they ran, the faster they became and passed this on to their offspring. B) Those cheetahs who ran fast were able to get food and survive and reproduce, passing this trait on to offspring. C) Through the survival of the fittest, slow cheetahs died. D) The environment chose fast cheetahs. Cheetahs were forced to run as fast as they could to catch prey; the more they ran, the faster they became and passed this on to their offspring. Lamarck believed in the inheritance of acquired characteristics, meaning that any behavior or trait acquired during an organism's lifetime would be passed on to offspring. Lamarck's theory is inaccurate. Darwin's theory of evolution by means of natural selection states that organisms most suited to the environment survive, reproduce, and pass these advantageous traits on to offspring. Those not well adapted die.

A) Cheetahs were forced to run as fast as they could to catch prey; the more they ran, the faster they became and passed this on to their offspring.

The graph shows the results of a famous biological experiment. In the experiment, Kettlewell believed that the peppered moth demonstrated how environmental pressures influence evolution. He studied two areas. Birmingham was a rural wood, with natural conditions. Dorset was an urban, industrial area. The moths use tree trunks to camouflage themselves against birds, which are their major predators. Natural gene variations produce a light form of the peppered moth, and a dark form, meaning that they are not equally visible. All BUT ONE statement is supported by Kettlewell's data. That is A) Dark moths had a survival disadvantage in industrial Dorset. B) Light moths had a survival advantage in forested Birmingham. C) Light moths had a survival disadvantage in industrial Dorset. D) Dark moths had a survival disadvantage in forested Birmingham. Dark moths had a survival disadvantage in industrial Dorset. After the introduction of industry, the dark moth population remained approximately the same in Dorset to Birmingham. However, the light moths in the rural area still had a much larger population.

A) Dark moths had a survival disadvantage in industrial Dorset.

Place the developments in evolutionary history in the proper time frame. I) Charles Darwin writes 'On the Origin of Species'. II) LaMarck writes about evolution through acquired traits, using a giraffe as his model. III) DNA sequencing is developed, allowing the comparison of the genes of different organisms. IV) Malthus, an economist, writes about the inevitability that people will exhaust a food supply by reproducing too often. A) IV, II, I, III B) I, II, IV, III C) II, I, IV, III D) II, I, III, IV IV, II, I, III Malthus (1798) inspired Darwin (1859) through his ideas, but in between these two events, LaMarck penned his own ideas (1809). DNA sequencing did not come along until the end of the 20th century.

A) IV, II, I, III

Bed bugs might sound like an old-fashioned problem, but now they are back with a vengeance. Fifty years ago, the blood-sucking pests were nearly eradicated in the United States thanks in part to the use of pesticides like DDT. Today, they are creeping over sheets and tormenting sleepers across the country. New York was recently declared America's most bed-bug-infested city in America. In the past, we countered the bed bugs by using pesticides called pyrethrins and pyrethroids. These compounds work by attacking the nervous system. Insects have channels in the membranes of their nerve cells that can be opened to allow sodium into the cells, triggering a nerve impulse. Pyrethrins and pyrethroids alter the nervous system by binding to the sodium channels, locking them in the open position. This allows sodium to pour into the cell continuously, causing the nerve to fire repeatedly and eventually leading to paralysis. Todays bed bugs seem to be more resistant to the chemicals. Biologists have determined that mutations are responsible for this resistance. Mutations changing just two of the 2000 amino acids that make up part of the sodium channels would be enough to make an insect 250 times more resistant to a commonly used pyrethroid. These mutations may change the channel so that the insecticide can no longer bind to it effectively. Explain how a mutation causing resistance to pyrethrins and pyrethroids would spread through a population of bed bugs that are being treated with the pesticide. A) In a population of bed bugs, variation exists. Some variation provides resistance to the pesticides. Those bed bugs survive to reproduce, passing the resistance on to offspring. B) Mutations happen randomly to change the gene pool of a population. The mutations are favored when a population of organisms winds up in an environment in which the mutations happen to be useful. C) When a population of insects, like bed bugs, is subjected to pesticides, some of the bed bugs alter their genetic make-up and they are able to survive. They then pass the new genes on to offspring. D) In any population of organisms, sexual reproduction provides for variation in the gene pool. Such variation allows some insects to be resistant to pesticides. When sexual reproduction occurs again, the resistance is passed to offspring. In a population of bed bugs, variation exists. Some variation provides resistance to the pesticides. Those bed bugs survive to reproduce, passing the resistance on to offspring. The steps to natural selections include: variation, selection, and inheritance. One other answer is a true statement; it just does not answer the question.

A) In a population of bed bugs, variation exists. Some variation provides resistance to the pesticides. Those bed bugs survive to reproduce, passing the resistance on to offspring.

The contraction of auricular muscles around the ear produces a range of motions in the ears of domesticated animals as well as the macaque monkey and most other monkeys. Thanks to these muscular motions, the ears act as antennae and can be used to sense danger and locate prey. Humans and other primates such as the orangutan and chimpanzee have ear muscles that are minimally developed and non-functional. How are these vestigial ear muscles an example of natural selection? A) In most primates the inability to move the ear has been replaced by the ability to turn the head on a horizontal plane as well as having peripheral vision. B) Most primates are not victims of predators and they are not predators themselves so they do not need this trait. C) In most primates the inability to move the ear has been replaced by the ability to stand upright on two legs. D) A muscle attached to the ear that cannot move the ear has no function. In most primates the inability to move the ear has been replaced by the ability to turn the head on a horizontal plane as well as having peripheral vision. The function of the movable ear has been replaced by the function of other parts of the muscular and sensory systems.

A) In most primates the inability to move the ear has been replaced by the ability to turn the head on a horizontal plane as well as having peripheral vision.

Peppered moths come in two colors, black and white. What did Kettlewell show, with regard to peppered moth populations and tree coloring? (Recall that England at the time was heated mainly by coal in urban areas.) A) In smoggy areas, dark moths have a higher survival rate than white moths. B) White moths stand out in rural areas, and quickly disappear from those areas. C) The black moth and white moth forms were actually two different species of moths. D) Environmental conditions do not affect physical features of a species over a short time period. In smoggy areas, dark moths have a higher survival rate than white moths. Kettlewell showed that the environment puts selection pressures on physical traits. In smoggy areas, dark moths hide from birds more effectively on tree trunks. In rural areas, trunks remain light and white moths do better.

A) In smoggy areas, dark moths have a higher survival rate than white moths.

Darwin observed how farmers and breeders produced many kinds of farm animals and plants. These plants and animals had traits that were desired by the farmers and breeders. He also noticed how the study of similar body structures and vestigial organs could add to the evidence of evolution. After performing several breeding experiments, he came to certain conclusions and formulated some theories. His theory of evolution and natural selection is the most accepted one. What is the reason behind the acceptance of Darwin's theory? A) It is supported by practical evidence and examples. B) It is supported by its harmonizing with other views. C) It is based on the ideas of earlier hypothesis and laws. D) It is based on the practical example of Lamarck's theory Darwin's theory It is supported by practical evidence and examples. Darwin explained each aspect of the theory with sufficient practical examples and is the most accepted theory of evolution.

A) It is supported by practical evidence and examples.

The carbon-14 isotope is important because it allows scientists to determine the ___________ of an organic sample. A) age B) density C) evolution D) mass Carbon-14 is the radioactive isotope that is used to help determine the age of an organic sample. The older the sample, the more the sample will have decayed, and the less radioactive it will be.

A) age

A scientist is interested in studying the growth pattern of dinosaur embryos. Which of these organisms is MOST likely to have an embryonic development pattern similar to an extinct dinosaur? A) alligator B) bat C) horse D) mouse A reptile like an alligator is most likely to be similar in development to an extinct dinosaur. The other choices are all mammals that are unlikely to have an embryological development like that of a dinosaur.

A) alligator

In evolutionary history, the first animals to successfully invade land from the sea were ___________________, an animal with a hard outer skeleton and jointed limbs. A) arthropods B) dinosaurs C) protists D) reptiles Arthropods. Arthropods,like insects and crabs, were (and still are) the most successful land dwelling animals. They were first to establish themselves on "dry" land.

A) arthropods

Green and brown algae share many common features. Both have pigments for trapping sunlight and use photosynthesis for energy. Both store their food as sugars. Both have cell walls and plant-like bodies. However, their DNA suggests that they are not even remotely related to one another. Green algae and brown algae show __________________ evolution, since they look similar, but are not close relatives. A) convergent B) divergent C) homologous D) vestigial Convergent. In convergent evolution, unrelated organisms develop similar features in response to similar pressures from the environment.

A) convergent

According to the theory of _____________, mitochondria in cells today are the descendents of aerobic prokaryotes that used oxygen to generate energy. A) endosymbiosis B) ingestion C) mutualism D) parasitism Endosymbiosis. According to endosymbiosis, mitochondria were once free-living organisms that became a permanent part of host cells.

A) endosymbiosis

Which characteristic is the most primitive and least evolved trait, with regard to plants? A) lack of vascular tissue B) seeds enclosed with cones C) use of spores instead of seeds D) separate sexes on different plants lack of vascular tissue. Mosses and liverworts, non-vascular plants, are the least evolved plants, and must remain near water, because they cannot 'wick' water up their stems.

A) lack of vascular tissue

Suppose a species of nonpoisonous snake is dark-colored, and a species of poisonous snake is brightly colored. Predators recognize the bright colors of the poisonous snake and stay away from it, but they frequently feast on the nonpoisonous snake. Some nonpoisonous snakes, like the king snake look a lot like a poisonous variety. In this case, the king snake looks like the deadly coral snake. The king snake is not attacked by predators and survives. A) mimicry. B) evolution. C) camouflage. D) variation. This adaptation that allows for natural selection is called mimicry. Predators avoid the king snake, even though it is nonpoisonous, and it survives to reproduce.

A) mimicry.

Which of these pairs of body structures BEST illustrates a homologous relationship? A) the leg of a horse and the leg of a dog B) the wing of a bat and the wing of a bird C) the fin of a dolphin and the fin of a shark D) the beak of a bird and the beak of a turtle The leg of a horse and the leg of a dog illustrates a homologous relationship. Homologous structures are structures that may look different but develop from the same embryological tissues and indicate a close evolutionary relationship.

A) the leg of a horse and the leg of a dog

The information contained in the table could be used _______________________. A) to establish the degree of relatedness among these organisms B) to determine which organisms underwent convergent evolution C) to show how protein shape determines function D) in comparative embryology studies to establish the degree of relatedness among these organisms The more similar the DNA, the greater the degree of relatedness, or the more recent in time the two organisms diverged from a common ancestor. If there is a great difference in DNA sequencing, this suggests that the organisms shared a common ancestor a long time ago.

A) to establish the degree of relatedness among these organisms

Whales are thought to have evolved from land animals similar to large otters. As evidence of this, whales have useless leg bones (structure C) that float inside their bodies. These leg bones are ___________ structures. A) vestigial B) homologous C) analagous D) evolutionary Vestigial. Vestigial structures are useless structural leftovers, such as wisdom teeth, appendixes, and tailbones in humans.

A) vestigial

A fossil of a fern and other large-leafed plants were found in an area of Alaska. What does this suggest about this area in Alaska? A) A forest is now covered with snow. B) A farm was once located in the area. C) The area once had a warmer climate. D) Prehistoric man ate large-leafed plants. The fossilized fern suggests the area once had a warmer climate.

C) The area once had a warmer climate.

The theory of endosymbiosis suggests that chloroplasts and mitochondria were once free-living prokaryotes, that were engulfed by larger prokaryotic cells. Eventually, this relationship lead to the development of eukaryotic cells with cellular organelles. These organelles included mitochondria, and in some cases, chloroplasts. The endosymbiosis theory is supported by all BUT one piece of modern-day evidence, which is both organelles A) contain DNA. B) contain ribosomes. C) are capable of living independently. D) are surrounded by a double membrane. The endosymbiosis theory is supported by all BUT one piece of modern-day evidence. That is both organelles are capable of living independently. Although both organelles contain RNA, DNA, and ribosomes, if extracted from eukaryotic cells, they are not capable of living independently.

C) are capable of living independently.

The human body contains structures that are needed for survival, or in the case of vestigial structures, were needed for survival. Wisdom teeth, seen here, are vestigial third molars. Human ancestors had larger jaws with more teeth. Over thousands of years, man no longer needed the third molar, and they became the source of dental problems rather than an aid in survival. How does this vestigial structure support the theory of natural selection? A) The six of man's cranial cavity evolved. With increased cranial cavity size, the size of man's brain also grew. This resulted in a smaller jaw and no room for the third molars. B) Agriculture and the use of fire changed what and how man ate and the need for these teeth diminished over time. Jaw size and shaped evolved and there was insufficient room for the third molars. C) The climate on Earth changed from very cold to tropical. The tropical climate on Earth lead to a change in the diet of humans and that lead to the need for sharp, pointed teeth rather than molars. D) The third molars erupt in the mouth later in the life of a human. As the life span of human ancestors increased, the need for these third molars decreased. Man was able to live a longer life without the molars. Agriculture and the use of fire changed what and how man ate and the need for these teeth diminished over time. Jaw size and shaped evolved and there was insufficient room for the third molars. The skulls of human ancestors had larger jaws with more teeth, which possibly helped to chew foliage and other raw plant parts. After the advent of agriculture 10 000 years ago as well as the use of fire to cook foods, softer human diets became the norm, including carbohydrate and high energy foods.

B) Agriculture and the use of fire changed what and how man ate and the need for these teeth diminished over time. Jaw size and shaped evolved and there was insufficient room for the third molars.

About 96% of the information in human DNA is found in gorilla DNA. This evidence supports which statement? A) Humans evolved from gorillas. B) Gorillas and humans diverged from a common ancestor. C) As gorillas evolve, they will become more similar to humans. D) Gorillas and humans are too different for meaningful genetic comparisons. Gorillas and humans diverged from a common ancestor. Similarities in DNA, according to evolutionary theory, point to a common ancestor.

B) Gorillas and humans diverged from a common ancestor.

The graph above was made by a biologist working in the Galapagos islands. The biologist examined the stomach contents of the ground finch, the leaf finch, and the cactus finch, to determine what foods they usually ate. The graph shows the average number of seeds of the 4 most common plant species found in the stomach of each type of bird. Based on the graph, which statement is correct about the relationship between the ground finch and the cactus finch? A) Neither species of finch has diet similarities to the leaf finch. B) Ground finches and cactus finches mostly occupy different feeding niches. C) Ground finches and cactus finches probably compete strongly for cactus seeds. D) Daisy seeds make up a large portion of the diet of both types of finch, so they both occupy the same niche. Ground finches and cactus finches mostly occupy different feeding niches. Ground finches mostly eat grass & daisy seeds, while cactus finches mostly eat agave and cactus seeds. There is not much of a niche overlap.

B) Ground finches and cactus finches mostly occupy different feeding niches.

Geologists discovered fossil evidence of mesohippus, an ancestor of the modern horse. Mesohippus lived in North America about 40 million years ago. Mesohippus was about two feet tall, ran on hooves with three toes, and had large, grinding teeth. What statement is BEST supported by the fossil evidence? A) Ancient horses were once carnivores. B) Horses have evolved over the last 40 million years. C) Horses migrated from South America into North America. D) Modern-day horses share a common ancestor with all mammals. Horses have evolved over the last 40 million years. Horses have changed over the last 40 million years; to change means to evolve. Horses are now much larger.

B) Horses have evolved over the last 40 million years.

Which statement is NOT a component of Darwin's original theory of evolution by natural selection? A) There is variation in all offspring. B) Humans and apes evolved separately from monkeys. C) All species over-reproduce to ensure their survival. D) Organisms with the most favorable traits tend to survive and reproduce at higher rates. Humans and apes evolved separately from monkeys. Darwin's theory of evolution by natural selection described the mechanisms of how evolution worked and did not describe any specific circumstances.

B) Humans and apes evolved separately from monkeys.

While on the Galapagos Islands, Darwin noticed that there were a number of species of finches that he theorized descended from a common ancestor. He hypothesized that these finches became isolated on an island and adapted to fit an ecological role on that island. What about the finches led Darwin to this belief? A) feather color B) body size C) beak shape D) mating behavior The finches evolved to have different beak shapes to be able to eat the food available on the different islands.

C) beak shape

Darwin hypothesized that there are definite steps to natural selection. Consider the model here. Use the Roman numerals (I - III) to guide you through the steps. Which is an accurate description of Darwin's hypothesized theory of natural selection? A) Sexual reproduction of bacteria cause variation. Some bacteria survive and some do not. Over time all of the bacteria should become extinct. B) In any population, variation exists. Some bacteria are resistant to antibiotics. Most bacteria die, but the bacteria that are resistant survive and reproduce. C) In a population of bacteria that are exposed to antibiotics, some bacteria change their genetic make-up and survive. The new genetic make-up is passed on to offspring. D) There is a change in the environment: an antibiotic is added. Some of the bacteria are capable of changing to the new environment. They survive and reproduce, passing along their favorable traits. In any population, variation exists. Some bacteria are resistant to antibiotics. Most bacteria die, but the bacteria that are resistant survive and reproduce. Most often, bacteria reproduce quickly using asexual reproduction. A mutation may cause the drug-resistance.

B) In any population, variation exists. Some bacteria are resistant to antibiotics. Most bacteria die, but the bacteria that are resistant survive and reproduce.

Which of these scientists is best known for his idea that characteristics an individual gains in its lifetime could be passed on to future generations, eventually leading to the creation of new species? A) Darwin B) Lamarck C) Linnaeus D) Mendel Lamarck believed in acquired characteristics. He believed that characteristics an individual gains in its lifetime can the be passed on to future generations. This was later proven to be untrue.

B) Lamarck

While visiting the Galapagos Islands in 1835, Charles Darwin collected over thirteen different species of a type of bird called a finch. He later observed that the birds were similar in many ways but often differed in the size and shape of their beaks. Which statement BEST summarizes Darwin's explanantion for the different beaks he observed in these finch species? A) The beaks changed so they could eat different foods. B) The beaks of each finch species were the result of natural selection. C) The size and shape of the beaks differed because of the effects of artificial selection. D) The size and shape of the beaks differed because of different climates found on the islands. The beaks of each finch species were the result of natural selection. Darwin believed that the shape and size of the beak were best suited for the environment in which the bird lived.

B) The beaks of each finch species were the result of natural selection.

Charles Darwin is well known for developing the theory of evolution based on his observations of the finches found on the Galapagos Islands. Which of these would be an example of how someone would explain why the finches had different beak sizes PRIOR to the ideas developed by Darwin? A) The differences in their DNA led to different beak sizes. B) The finches have always had different beak sizes and that has never changed throughout time. C) The finches continue to slowly change today based on the slight differences found within the population. D) The variations within the finch population led to certain individuals being better fit to survive in different conditions. Prior to Darwin, one might have believed that the finches have always had different beak sizes and that has never changed throughout time. It was believed that all organisms appeared on earth at the same time and have never changed,. Darwin helped pave the way to showing that organisms do change over time, and it is due to the slight changes found within the population.

B) The finches have always had different beak sizes and that has never changed throughout time.

The snowshoe rabbit has white fur in winter and dark fur in summer. What is the main survival advantage of this fur color change to the rabbit? A) The light fur keeps the rabbit from getting sunburned in summer. B) The fur color is an adaptive form of camouflage to avoid predators. C) The dark fur absorbs more sunlight so the rabbit is warmer in winter. D) The white fur is more valuable to fur trappers, so the animal will be trapped and better fed in winter. The fur color is an adaptive form of camouflage to avoid predators. The rabbit is dark during summer to blend in with foliage, and light during winter, to blend in with snow.

B) The fur color is an adaptive form of camouflage to avoid predators.

A population of green iguanas lived on a tropical island. Originally, most of the iguanas had feet without webbing between their toes and a long round tail. A few iguanas had webbed feet and a short, flat tail. As the years passed, the island became smaller and smaller because of flooding. Even the land areas were dotted with ponds and pools. The iguanas had a hard time finding the food they normally ate. To survive, the iguanas had to swim from island to island to find food. How would you expect the iguanas to look many years after the island flooded and food became harder to find? A) The iguanas will look the same but there will be less of them. B) There would be more iguanas with webbed feet and flat tails. C) There would be fewer iguanas with webbed feet. D) The iguanas would no longer be green. There would be more iguanas with webbed feet and flat tails. Because iguanas now had to swim to find food, the iguanas that had webbed feet and short, flat tails were able to survive and reproduce. Over time, more and more iguanas had webbed feet and flat tails.

B) There would be more iguanas with webbed feet and flat tails.

According to scientists, the organisms in the picture all evolved from a common ancestor. What evidence backs up this theory? A) These organisms are all of the same species. B) These organisms contain very similar bone anatomy. C) The appendages of these organisms share similar function. D) These organisms all lived in similar habitats and were therefore under similar environmental pressures. These organisms Contain very similar bone anatomy.. These organisms share common structure (homologous structures) due to the fact that they all evolved from a common ancestor.

B) These organisms contain very similar bone anatomy.

Scientists believe that the first life forms to appear on planet Earth were probably similar to which modern organisms? A) viruses B) bacteria C) plant cells D) animal cells Scientists believe that the first organisms to appear on Earth most likely resembled modern bacteria. This is due to the simplicity of these organisms.

B) bacteria

All but one term describes a type of natural selection. _____________ selection is NOT a type of natural selection. A) directional B) disruptive C) distributed D) stabilizing Distributed. Distributed selection is not found among the types of natural selection.

C) distributed

Chemical analysis of the oxygen isotopes in foraminifera shells allow scientists to create a climate record like the one shown here. The chemical composition of shells depends on the temperature of the surrounding water and the presence or absence of large polar ice sheets. Fossil data like this indicates that A) only simple organisms on Earth are subject to change over time. B) climatic changes can definitely influence changes in life forms. C) change in life forms is more likely to change in marine habitats. D) climatic change does not necessarily result in change in life forms. Fossil data like that illustrated here indicates that climatic changes can definitely influence changes in life forms. Scientists believe that climatic change and change in life forms go hand-in-hand. A similar foraminifera fossil record was used to study climate change around the time of the extinction of the dinosaurs to formulate a hypothesis for their disappearance.

B) climatic changes can definitely influence changes in life forms.

According to evolutionary theory, the cell on the right appeared first. _________________ were among the first photosynthetic forms of this organism. A) algae B) cyanobacteria C) plants D) zooplankton Cyanobacteria. Cyanobacteria were photosynthetic and supplied oxygen to an oxygen deficient environment.

B) cyanobacteria

If you have ever been to a natural history museum, you have probably seen large fossils of dinosaurs. These fossils are not actually bones, but hardened minerals which have replaced the bone over time. Despite the fact that we have a record of these ancient animals, they no longer roam the earth, due to ____________. A) adaptation B) extinction C) extraction D) pollution extinction Sometimes species change slowly over time, but sometimes they can die off altogether.

B) extinction

Which term describes body structures in different organisms that have different outward appearances but develop from the same embryonic tissues? A) analogous B) homologous C) remedial D) vestigial Homologous structures is the term used to describe body structures in different organisms that have different outward appearances but develop from the same embryonic tissues.

B) homologous

Identify the BEST way to determine if two organisms are closely related. A) comparing body plans B) molecular homology (comparing DNA) C) identifying and comparing homologous structures D) comparative embryology (comparing embryonic development) molecular homology (comparing DNA) Although all of answers, if similar, would suggest degrees of relatedness, the BEST way to determine how closely two organisms are related is through DNA comparison. The more similar the DNA, the greater the degree of relatedness.

B) molecular homology (comparing DNA)

The fossil image is of a trilobite. Trilobites lived in the ancient seas and the fossil was found in the sea floor. Compare the fossil to the four modern-day animals also pictured. Based on physical evidence, the trilobite is probably a direct ancestor of what animal? A) locust B) pillbug C) scallop D) roundworm pillbug If you compare the shape of the body and pattern of the exoskeleton, you will see the similarities.

B) pillbug

According to Darwin, organisms that are best adapted to their environment are more likely to produce offspring than organisms that are less well adapted to their environment. Which phrase is used to summarize this idea? A) species variability B) survival of the fittest C) use and disuse of organs D) evolution through mutation Survival of the fittest refers to the observation by Darwin that organisms that are better adapted to their environment ('more fit') are more likely to survive and reproduce than organisms less well adapted.

B) survival of the fittest

Thomas Malthus' most well known work An Essay on the Principle of Population was published in 1798, although he was the author of many pamphlets and other longer writings. The main ideas of his argument on the human condition were radically opposed to current thinking at the time. He argued that increases in population would eventually diminish the ability of the world to feed itself and based this conclusion on the thesis that populations expand in such a way as to overtake the development of sufficient land for crops. The main idea of Malthus' article as described above is analogous to A) Lamarck's theory of use and disuse. B) the concept of population and carrying capacity. C) Darwin's ideas regarding survival of the fittest. D) the belief that inherited variations in a population increase an individual's ability to compete, survive, and reproduce. The main idea of Malthus' article as described above is analogous to the concept of population and carrying capacity. Malthus' view was that poverty and famine were natural outcomes of population growth and a limited food supply. Any population requires a certain amount of natural resources in order to survive. If any of the basic resources are limited, survival declines.

B) the concept of population and carrying capacity.

Natural selection would favor which of the these rabbits in Antarctica? A) brown rabbit B) white rabbit C) black rabbit D) white-and-black rabbit A white rabbit would be favored by natural selection in Antarctica because it would blend into the snow covering the land. By blending in, the white rabbit would avoid predators, and reproduce more successfully than other color rabbits.

B) white rabbit

How can a geological time scale BEST be reconstructed? A) comparing vestigial structures in living species B) comparing homologous structures in living species C) examining homologous structures in fossil remains D) examining the written records of scientists from past cultures examining homologous structures in fossil remains It is possible to get an idea of how things change and evolve by comparing how fossils change over time.

C) examining homologous structures in fossil remains

There have been many attempts over time to explain the mechanism behind the evolution of living organisms. Two of the better known theorists include Charles Darwin and Jean Baptist Lamarck. How would Lamarck's explanation of the evolution of long necked giraffes differ from Darwin's explanation? A) According to Lamarck, giraffes evolved due to environmental pressures; those giraffes with better traits would pass on traits to offspring, and according to Darwin, inherited traits were passed to offspring. B) Since they both believed in the same mechanism for evolution, both would agree that long necked giraffes evolved because the more giraffes stretched their necks, the better fit for the environment, and this trait was passed down to offspring. C) According to Lamarck, long necked giraffes evolved because they spent the majority of their time stretching their necks and this trait was passed down to offspring; according to Darwin, giraffes with longer necks had the advantage in the environment and survived, reproduced, and passed this trait on to offspring. D) According to Darwin, long necked giraffes evolved because they spent the majority of their time stretching their necks and this trait was passed down to offspring; according to Lamarck, giraffes with longer necks had the advantage in the environment and survived, reproduced, and passed this trait on to offspring. According to Lamarck, long necked giraffes evolved because they spent the majority of their time stretching their necks and this trait was passed down to offspring; according to Darwin, giraffes with longer necks had the advantage in the environment and survived, reproduced, and passed this trait on to offspring. Lamarck believed in the inheritance of acquired characteristics, meaning that any behavior or trait acquired during an organism's lifetime would be passed on to offspring. Darwin believed that the organisms most suited to the environment survived, reproduced, and passed these advantageous traits on to offspring. Those not well adapted died.

C) According to Lamarck, long necked giraffes evolved because they spent the majority of their time stretching their necks and this trait was passed down to offspring; according to Darwin, giraffes with longer necks had the advantage in the environment and survived, reproduced, and passed this trait on to offspring.

James was sick, went to the doctor, and was diagnosed with a bacterial throat infection. His infection was treated with antibiotics. In a few days, James felt much better, but some resistant bacteria survived and, overnight, James was sick again. This time, he had to take a much stronger antibiotic. The resistant bacterial cells illustrate what characteristic of life? A) All living things respond to stimuli. B) All living things maintain homeostasis. C) All living things adapt to changes in their environment. D) All living things contain genetic material and reproduce. All living things adapt to changes in their environment. This is one part of the evolution picture. The "new" bacteria in this situation were resistant to the first antibiotic and survived. They will pass this resistance to their off-spring.

C) All living things adapt to changes in their environment.

All of the following EXCEPT the resistance of _________ demonstrate artificially selected resistance. A) beef cattle, to "shipping fever", B) many agricultural wheat varieties, to drought and fungus, C) Antarctic fish to freezing, due to antifreeze proteins in their blood, D) many common grasshopper species to pesticides, such as diazinon, sevin, and others, The resistance of Antarctic fish to freezing, due to antifreeze proteins in their blood. This is the only answer choice where natural selection is working, and not artificial selection by human means.

C) Antarctic fish to freezing, due to antifreeze proteins in their blood,

Four species of finch arrive on a newly formed Galapagos island, which is covered with cacti growing in loose, dry sand. The cacti have honey-filled flowers and tiny seeds. The theory of evolution by natural selection would probably predict that ____________________ would most succesfully survive, because _________________________. A) Geospiza magnirostris; its large size makes it the fittest. B) Geospiza fortis; it will probably be able to dig up worms with its bill. C) Certhidia oliveacea; its tiny pointed bill is the best adapted to sip nectar. D) Geospiza parvula; animals with intermediate traits tend to have higher survival rates in new places. Certhidia oliveacea; its tiny pointed bill is the best adapted to sip nectar. This finch is the most fit to survive in its new environment.

C) Certhidia oliveacea; its tiny pointed bill is the best adapted to sip nectar.

Scientists routinely explore whether two different animal species have evolved from a recent common ancestor. _______________ is the LEAST useful technique to help with this determination. Comparison of items eaten for food is the least useful technique for determining whether two species share a recent common ancestor. Studies of embryological development, anatomical comparisons, and DNA analysis are all tools used to determine the relationships among animal species. A) Analysis of strands of DNA B) Comparisons of bones and muscles C) Comparisons of items eaten for food D) Studies of embryos during development Comparison of items eaten for food is the least useful technique for determining whether two species share a recent common ancestor. Studies of embryological development, anatomical comparisons, and DNA analysis are all tools used to determine the relationships among animal species.

C) Comparisons of items eaten for food

The MOST accurate way to determine the evolutionary relationship between two animals is through the examination of A) common behaviors. B) similar physical features. C) DNA or protein sequences of shared genes. D) fossilized ancestors that they may have in common. DNA or protein sequences of shared genes. Biochemical evidence is extremely accurate in determining the relationship between two organisms. Many animals have been re-classified, due to DNA evidence.

C) DNA or protein sequences of sared genes.

The amino acids for beta hemoglobin found in five species were compared to the amino acids found in human (Homo sapiens) beta hemoglobin. The number of sequence differences was recorded. Based on the molecular data, which species is most closely related to humans? A) Lemur catta (lemur) B) Hylobates lar (gibbon) C) Gorilla gorilla (gorilla) D) Macaca mulatta (Rhesus monkey) Gorilla gorilla (gorilla) There is only one difference in the amino acid sequences between humans and gorillas. Therefore, they would be considered most closely related. Least related would be the lemur.

C) Gorilla gorilla (gorilla)

Hummingbird bill length data was collected and graphed in a particular environment. Based on the data collected, which is the BEST conclusion drawn? A) The environment is selecting against all longer bill length birds. B) Due to natural selection, a virus has killed off all medium bill length birds. C) The environment has a greater amount of long nectar tubed flowers and short nectar tubed flowers causing disruptive selection in medium bill length birds. D) The environment has a greater amount of long nectar tubed flowers and short nectar tubed flowers causing stabilizing selection in medium bill length birds. The environment has a greater amount of long nectar tubed flowers and short nectar tubed flowers causing disruptive selection in medium bill length birds. Disruptive selection, also called diversifying selection, describes changes in population genetics in which extreme values for a trait are favored over intermediate values. In this case, the variance of the trait increases and the population is divided into two distinct groups.

C) The environment has a greater amount of long nectar tubed flowers and short nectar tubed flowers causing disruptive selection in medium bill length birds.

In 1831, Charles Darwin visited the Galapagos Islands. While observing the giant land tortoises that lived on these islands, Darwin noted that the shape of the tortoise shell varied depending on which island the tortoise lived. Tortoises on one island had round shells, for example, whereas tortoises on a neighboring island had more flattened, saddle-shaped shells. Which statement BEST summarizes Darwin's explanation for these differences? A) Random mutations caused the shape of the shells to fluctuate periodically. B) The shape of the tortoise shell varied because the predators on the islands were all similar. C) The particular shape of the shell was best suited for the island on which the tortoise was living. D) Tortoises who used their shells in special ways caused the shells to become larger, rounder, or flatter. The particular shape of the shell was best suited for the island on which the tortoise was living. Darwin reasoned that the particular shape of the shell was related to the ability of the tortoise to survive and reproduce.

C) The particular shape of the shell was best suited for the island on which the tortoise was living.

An earthquake causes a huge canyon to form, permanently dividing a population of wild donkeys. On the windward side of the canyon, dry conditions develop and grasses grow. On the leeward side of the canyon, rainfall is frequent and a forest grows. What is LEAST likely to happen over the course of 100,000 years? A) Two new species of donkeys will form. B) Donkeys from the grassy side could develop zebra striping for camouflage. C) The two populations of donkeys will remain physically identical in both areas. D) Over a long time, even if introduced to each other, donkeys from the grassy side of the canyon, will not be able to reproduce with donkeys on the forest side. The two populations of donkeys will remain physically identical in both areas. The two groups of donkeys will probably undergo speciation and adapt to the two new environments differently.

C) The two populations of donkeys will remain physically identical in both areas.

Why are the beak sizes and shapes of Darwin's finches different? A) They had different ancestors. B) They adapted to the type of predators. C) They adapted to the type of food available. D) They crossbred with different bird species. The beaks of Darwin's finches are different because of the type of food available. Large beaks are better for islands with larger seeds, while pointed beaks are better for getting insects out of trees.

C) They adapted to the type of food available.

Data was collected concerning Galapagos bird beak size over time. There are 13 types of Galapagos finches, and they are also known as Darwin's Finches. These finches share the same habits and characteristics except for one; they all have different beaks. The differences in their beaks might be the most important aspect of their survival because beak size determines the type of seed able to be eaten. Only the birds with the largest of beaks are able to eat the toughest, biggest, and spine covered seeds. Based on the data given, choose the BEST conclusion. A) This data shows that over time the type of food available remained constant. B) This data shows that the environment did not change over the course of time. C) This data shows a fluctuation in bird species over time most likely due to food availability. D) This data shows a fluctuation in bird species over time most likely due to the inheritance of acquired characteristics. This data shows a fluctuation in bird species over time most likely due to food availability. Percentages are based on environmental pressures. In the years with more birds with a larger beak size, the majority of the food available were big, tough, spine covered seeds. Those birds with a larger beak size survived better during those years. In natural selection, those animals most suited or best adapted to the environment survive and reproduce.

C) This data shows a fluctuation in bird species over time most likely due to food availability.

Evolution is a process by which species change over the years. Various views explaining how evolution takes place have been proposed by scientists across the decades. Though most of these theories have been discarded, those of two scientists have been supported by different segments of the scientific community. Jean-Baptiste Lamarck proposed the theory of inheritance of acquired characteristics to explain the process of evolution. It suggests that an organism can change itself willfully and pass on the acquired characteristics to the next generation or its offspring. Individuals develop traits that are useful and discard others that are not according to a predefined plot. Lamarck combined these two thoughts in his theory and substantiated them by evidence. One piece of evidence cited by him was that of the giraffe's long neck. He said that giraffes stretched their necks to reach leaves on branches of high trees, and this gradually lengthened their necks over time. This acquired trait of a long neck was inherited by their offspring, and thus all giraffes now have long necks. If you were to debate Lamarck today about his theory, what core concept in biology would you rely on? A) Organisms lacking favorable traits will become extinct. B) Mutations do not result in beneficial genetic variation. C) Traits cannot be chosen willfully, but are randomly inherited from our parents. D) Environmental stresses cause organisms to change, regardless of their genetic make-up. Traits cannot be chosen willfully, but are randomly inherited from our parents. Those that inherit favorable traits to a specific situation are more likely to survive and reproduce.

C) Traits cannot be chosen willfully, but are randomly inherited from our parents.

Some people believe that humans have always existed as the species we see today. Darwin created the theory of evolution. Which observation bolsters the theory of evolution? A) comparing vestigial structures in living species B) comparing homologous structures in living species C) examining homologous structures in fossil remains D) examining the written records of scientists from past cultures examining homologous structures in fossil remains It is possible to get an idea of how things change and evolve by comparing how fossils change over time.

C) examining homologous structures in fossil remains

Many species of organisms are found only on islands. Lemurs are found only on Madagascar and koalas only on Australia. Which factor contributes MOST to this situation? A) small land area B) fewer predators C) genetic isolation D) limited food variety Genetic isolation.This allows evolution to take directions independent of what is happening on the mainland. Since the animals of the island rarely migrate or have migrants, they exist as an independent ecosystem.

C) genetic isolation

Charles Darwin theorized that evolution must occur slowly, over long periods of time. This is a(n) _________ theory. A) catastrophist B) creationist C) gradualist D) punctuated gradualist Slowly, surely, this is a GRADUAL way to change.

C) gradualist

Despite their differences in appearance, all bony fish have common ancestors. Their fins develop from similar structures and usually have a prescribed number of bones. Because of this, the large rudder-like dorsal fin of a sailfish, the poisonous dorsal fin of a catfish, and the tiny reduced dorsal fin of a puffer fish are said to be ________ structures. A) vestigial B) analagous C) homologous D) evolutionary Homologous structures. These are traits, though different in appearance and function, that are derived from the same ancestral trait during development.

C) homologous

According to the fossil record, five ________________ took place, which lowered the variety of species found on Earth today. A) mass clonings B) microevolutions C) mass extinctions D) mass revolutions Mass extinctions. Mass extinctions resulted in the death of many species.

C) mass extinctions

When an existing population of organisms gives rise to two or more new species, the new species cannot effectively breed with one another. Which term is used to describe this phenomenon? A) adaptive seclusion B) species limitation C) reproductive isolation D) behavioral modification When new species are formed, they can no longer interbreed. This is called reproductive isolation.

C) reproductive isolation

For a given species, an increased evolutionary rate would cause a decrease in A) biodiversity. B) fitness of a species. C) similarity of the individuals in the species. D) the number of new genes in the DNA of the species. Similarity of the individuals in the species. It would be expected that increased evolutionary rate would cause individuals in the species to resemble each other less.

C) similarity of the individuals in the species.

In a field of sunflowers, there are varying heights. A plant breeder is determined to breed out all of the extremely tall and extremely short plants. His goal is to create a population of sunflowers that are all of average height. In terms of natural selection, we would call this _________ selection. A) directional B) disruptive C) stabilizing D) suggestive This is an example of stabilizing selection. This happens when selective pressures select against the two extremes of a trait, in this case, tall or short plants.

C) stabilizing

In 1850 there was a large snowshoe rabbit population in Manitoba, Canada. Over the years, the winter coloration (the color of the rabbit's fur) of the surviving rabbit population changed. The graph shows the change in winter coloration of rabbits between 1850 to 2000. Based on the data, we could hypothesize that A) the winters are longer in length. B) the snowshoe rabbit has migrated to another area. C) the amount of snow cover varied over the years. D) more snowshoe rabbit predators have moved into Manitoba. Based on the data, we could hypothesize that the amount of snow cover varied over the years. Winter white coloration is an adaptation for survival in snowy areas. If more gray rabbits are surviving, then there must be less snow.

C) the amount of snow cover varied over the years.

Naturalist Jean-Baptiste Lamarck promoted the theory of "inheritance of acquired characteristics." This theory stated that changes developed over the course of the life of an organism would be transmitted to the next generation. A famous example involves a blacksmith. Working with heavy hammers, pounding iron all day, blacksmiths developed larger arms than average men. This trait, large and muscular arms, would then be passed down to the children of the blacksmith. Charles Darwin developed a competing theory based on variation and a process he called "natural selection." His theory stressed how the differences among the individuals in a population would lead to different rates of survival and reproduction. Through this process, in conjunction with what he called a "strong principle of inheritance," entire populations could adapt, and ultimately, evolve. DNA and its structure was not isolated and understood until the mid 1900s. It serves as A) the mechanism through which population evolution operates. B) an example of how the blacksmiths arms grow as large as they do. C) the mechanism by which the "strong principle of inheritance" operates. D) the mechanism by which the "inheritance of acquired characteristics" operates. The correct answer is the mechanism by which the "strong principle of inheritance" operates. DNA is the substance passed from one generation to the next, determining which traits are present.

C) the mechanism by which the "strong principle of inheritance" operates.

Naturalist Jean-Baptiste Lamarck promoted the theory of "inheritance of acquired characteristics." This theory stated that changes developed over the course of the life of an organism would be transmitted to the next generation. A famous example involves a blacksmith. Working with heavy hammers, pounding iron all day, blacksmiths developed larger arms than average men. This trait, large and muscular arms, would then be passed down to the children of the blacksmith. Charles Darwin developed a competing theory based on variation and a process he called "natural selection." His theory stressed how the differences among the individuals in a population would lead to different rates of survival and reproduction. Through this process, in conjunction with what he called a "strong principle of inheritance," entire populations could adapt, and ultimately, evolve. DNA and its structure was not isolated and understood until the mid 1900s. It serves as Naturalist Jean-Baptiste Lamarck promoted the theory of "inheritance of acquired characteristics." This theory stated that changes developed over the course of the life of an organism would be transmitted to the next generation. A famous example involves a blacksmith. Working with heavy hammers, pounding iron all day, blacksmiths developed larger arms than average men. This trait, large and muscular arms, would then be passed down to the children of the blacksmith. A) the mechanism through which population evolution operates. B) an example of how the blacksmiths arms grow as large as they do. C) the mechanism by which the "strong principle of inheritance" operates. D) the mechanism by which the "inheritance of acquired characteristics" operates. The correct answer is the mechanism by which the "strong principle of inheritance" operates. DNA is the substance passed from one generation to the next, determining which traits are present.

C) the mechanism by which the "strong principle of inheritance" operates.

Scientists have studied the fossilized shells of prehistoric, single-celled marine organisms. Some of these shells were thin, which indicates that the organisms lived in very warm ocean water. Such evidence indicates that the climate during this time may have been A) moderate B) arctic. C) tropical. D) the same as it is today. If the shells were very thin and the oceans were very warm, the climate was most likely tropical. If the ocean waters were very cold, the organisms would have had thick shells to protect them from the cold.

C) tropical.

Which statement BEST explains Lamarck's theory of acquired characteristics as it relates to the neck length of giraffes? A) The DNA of the giraffe coded for longer necks in some individuals. B) The variation in giraffe neck sizes led to some being more fit and able to survive. C) Giraffes have always had long necks and this is not a characteristic that has ever changed. D) Giraffes slowly stretched their necks to reach leaves higher in the tree and over time their necks got longer. The idea of acquired characteristics would state that the giraffes slowly stretched their necks to reach leaves higher in the tree and over timetheir necks got longer. It was later determined that Lamarck's idea was untrue, and it actually based on the variations in the neck size of the giraffe's which led to more fit individuals.

D) Giraffes slowly stretched their necks to reach leaves higher in the tree and over time their necks got longer.

When the first antibiotics became available in the late 1940s and early 1950s, these antibiotics were effective against all bacterial infections. Today however, there are a multitude of antibiotic resistant bacterial infections. What conclusion can be drawn? A) Antibiotics of today are not as strong as those in the past. B) Antibiotics cause DNA mutations in bacteria, and over time, this has led to resistance. C) Over time, bacteria have turned into viruses, and antibiotics have no affect over viruses. D) Bacteria have become resistant to antibiotics over time due to evolution by means of natural selection. Bacteria have become resistant to antibiotics over time due to evolution by means of natural selection. When taking antibiotics, those bacteria that can be killed by antibiotics will die. However, due to random DNA mutations, some bacteria cells may be resistant to antibiotics. These resistant forms are the ones to survive, reproduce, and pass on their genes.

D) Bacteria have become resistant to antibiotics over time due to evolution by means of natural selection.

Some people believe that humans have always existed as the species we see today. Darwin created the theory of evolution. Which observation bolsters the theory of evolution? A) Humans have very diverse traits today. B) There appear to be missing links in the evolutionary chain. C) Life on earth has been found to date back billions of years. D) DNA found in older primate fossils resemble those of humans today. DNA found in older primate fossils resemble those of humans today. With this information, scientists can assume that there is a link between modern humans and these older fossils.

D) DNA found in older primate fossils resemble those of humans today.

Giraffes were the subject of debate in the early days of evolutionary theory. LaMarck believed in acquired characteristics, while Darwin believed in evolution by natural selection. Which is an accurate match between the author, and how he would explain the long neck of giraffes? A) LaMarck believed that giraffes were created with long necks and remained unchanged from their original design. B) Darwin believed that giraffes could stretch their necks to reach leaves and then pass this trait on to their offspring. C) LaMarck believed that over time, shorter giraffes were starved out and giraffes with longer necks survived to reproduce. D) Darwin believed that giraffes with longer necks had a higher survival rate, due to ease of feeding and reproduction, and this is the way giraffes evolved. Darwin believed that giraffes with longer necks had a higher survival rate, due to ease of feeding and reproduction, and this is the way giraffes evolved. This is consistent with evolution by natural selection, 'survival of the fittest'.

D) Darwin believed that giraffes with longer necks had a higher survival rate, due to ease of feeding and reproduction, and this is the way giraffes evolved.

Jimmy believed that if he exercised every day his children would be born healthy and fit. Being an avid student of biology, what comment would you make about Jimmy's belief? A) It is a true statement and Jimmy's children will be healthier. B) It is true but would be better if Jimmy's wife was included in the exercise program. C) Jimmy is partially correct; he should also eat healthy foods in order to have healthy, fit children. D) It is untrue as characteristics you acquire in your lifetime cannot be passed on to future generations. It is untrue as characteristics you acquire in your lifetime cannot be passed on to future generations.. Lamarck believed that you could acquire characteristics and then pass them on to future generations. Darwin's theory of natural selection and survival of the fittest helped prove this theory to be false.

D) It is untrue as characteristics you acquire in your lifetime cannot be passed on to future generations.

Naturalist Jean-Baptiste Lamarck promoted the theory of "inheritance of acquired characteristics". This theory stated that changes developed over the course of the life of an organism would be transmitted to the next generation. A famous example involves a blacksmith. Working with heavy hammers, pounding iron all day, blacksmiths developed larger arms than average men. This trait, large and muscular arms, would then be passed down to the children of the blacksmith. Charles Darwin developed a competing theory based on variation and a process he called "natural selection". His theory stressed how the differences among the individuals in a population would lead to different rates of survival and reproduction. Through this process, in conjunction with what he called a "strong principle of inheritance", entire populations could adapt, and ultimately, evolve. The fact that many blacksmith apprentices were not born to blacksmith fathers, and they still developed large arms, would have what impact on Lamarck's theory? A) According to his theory, it would mean that the apprentice's children would definitely have large arms. B) It would weaken it somewhat, because it shows that physical characteristics are mostly linked to one's environment. C) It would strengthen the theory, because of the clear connection between being a blacksmith and having certain physical traits. D) It would weaken it, because it suggests that development of some traits may not be linked to the characteristics of one's parents. It would weaken it, because it suggests that development of some traits may not be linked to the characteristics of one's parents. This is the best answer because it directly refutes Lamarck's claim, that acquired traits are passed down from parents to children.

D) It would weaken it, because it suggests that development of some traits may not be linked to the characteristics of one's parents.

In 1950's, Stanley Miller and Harold Urey showed how organic molecules necessary for the formation of life could be assembled from simple molecules known to have existed on Earth millions of years ago. Evidence from Miller and Urey's experiments suggest that complex organic molecules could be formed from other, simpler molecules. Why is it unlikely that this process is still occuring today? A) Modern amino acids are unlike those that may have existed on the ancient Earth. B) The current environment of the Earth is too polluted to allow the formation of organic molecules. C) The present day Earth lacks sufficient energy to allow the formation of organic molecules to occur. D) Living organisms such as bacteria are likely to interfere in the process by breaking down the organic molecules. Evidence from Miller and Urey's experiments suggest that complex organic molecules could be formed from other, simpler molecules. Why is it unlikely that this process is still occuring today?

D) Living organisms such as bacteria are likely to interfere in the process by breaking down the organic molecules.

For over a decade, farmers in the U.S. have been planting genetically modified crops. An example of one of these crops is corn that is resistant to weed-killer. This makes it so that no corn is lost due to contact with herbicide meant to kill weeds. While this is seen by many as a positive development, others see it as a cause for concern. What is one possible negative side effect of planting genetically modified corn? A) Genetically modified corn, as well as other plants, is unnatural. B) Corn will replace wheat and other crops as our main source of carbohydrates. C) Plants with modified genomes may have a predictable impact on the environment. D) Plants with modified genomes may have an unforeseen impact on the environment. Plants with modified genomes may have an unforeseen impact on the environment. Even though the genetic modification may seem small, how it interacts with an environment outside the lab is nearly impossible to predict.

D) Plants with modified genomes may have an unforeseen impact on the environment.

Which pair of organisms show convergent evolution? A) Despite being close relatives, cattle and giraffes have drastically different neck lengths. B) Ducks develop different mating dances to avoid mating with other ducks from different species. C) A bluegill sunfish and a redear sunfish, closely related, have similar fin shapes and color patterns. D) Tasmanian devils and wolverines are both thick-bodied predators with crushing teeth and similar food sources, but they are not at all related. Tasmanian devils and wolverines are both thick-bodied predators with crushing teeth and both eat carrion, but they are not at all related. In convergent evolution, unrelated organisms adapt similar features to deal with similar environments.

D) Tasmanian devils and wolverines are both thick-bodied predators with crushing teeth and similar food sources, but they are not at all related.

A population of fruit flies on an island lay their eggs in some rotting fruit. Some of the fruit is blown into the ocean by a storm and washes up on another island that is too far apart for the flies to fly back to their original island. Over time the two populations change so much that they are different species. What must be true of the two populations of flies at this point? A) They will be genetically identical. B) They will share no genetic material. C) They will be able to produce fertile offspring. D) They will not be able to produce fertile offspring. Different species are not able to produce fertile offspring with one another.

D) They will not be able to produce fertile offspring.

Look at the picture showing the difference between punctuated equilibrium and gradualism. What provides the best evidence for gradualism? A) Mass extinctions B) Adaptive radiation C) Convergent evolution D) Transitional fossils Transitional fossils Gradualism is the idea that large changes are actually the culmination of very small changes that build up over time. Transitional fossils are fossils in the record that show structural adaptations of species as they transform into new species slowly over time. Punctuated equilibrium is based on the idea that we see a quick burst of change in a species and then very long periods of no change.

D) Transitional fossils

Bed bugs might sound like an old-fashioned problem, but now they are back with a vengeance. Fifty years ago, the blood-sucking pests were nearly eradicated in the United States thanks in part to the use of pesticides like DDT. Today, they are creeping over sheets and tormenting sleepers across the country. New York was recently declared America's most bed-bug-infested city in America. In the past, we countered the bed bugs by using pesticides called pyrethrins and pyrethroids. These compounds work by attacking the nervous system. Insects have channels in the membranes of their nerve cells that can be opened to allow sodium into the cells, triggering a nerve impulse. Pyrethrins and pyrethroids alter the nervous system by binding to the sodium channels, locking them in the open position. This allows sodium to pour into the cell continuously, causing the nerve to fire repeatedly and eventually leading to paralysis. Todays bed bugs seem to be more resistant to the chemicals. Biologists have determined that mutations are responsible for this resistance. Mutations changing just two of the 2000 amino acids that make up part of the sodium channels would be enough to make an insect 250 times more resistant to a commonly used pyrethroid. These mutations may change the channel so that the insecticide can no longer bind to it effectively. If bed bugs had never been exposed to DDT in the 1950's and 1960's, how would you expect that to affect bed bugs' resistance to pyrethroids during the last decade? A) Because bed bugs reproduce so rapidly, resistance to pyrethroids among bed bugs has become a major problem. B) With the widespread use of DDT, pesticide-resistant mutations became much more common among bed bugs. The bed bugs passed that resistance on to future generations. C) If some of the bed bugs carry the resistance mutations, those insects will be better able to survive and reproduce and will wind up passing the mutation on to their offspring. D) Without the use of DDT, natural selection would not have favored any mutations that provided protection from pesticides; bed bugs would be more susceptible to today's chemicals. Without the use of DDT, natural selection would not have favored any mutations that provided protection from pesticides; bed bugs would be more susceptible to today's chemicals. Without the DDT spraying, the mutation might not have been favored and todays bed bugs would be less resistant to modern sprays.

D) Without the use of DDT, natural selection would not have favored any mutations that provided protection from pesticides; bed bugs would be more susceptible to today's chemicals.

Scientists believe that land plants, such as the examples seen here, evolved from single-celled green algae. Single-celled algae first evolved a colonial form, as noted in Volvox, and eventually developed organs for reproduction as well as food and water conduction. One key process in this evolution was A) mitosis. B) cell replication. C) genetic continuity. D) cell differentiation. In order to evolve from a single celled aquatic photosynthetic organism to a multicellular land plant, many changes needed to take place. The first place the changes began was with cell differentiation. In a typical land plant, there are many types of cells that have various functions. Some cells are organized into tissues and organs. We can see this process at work today when undifferentiated cells, or meristems, are used in vegetative propagation. These undifferentiated cells are capable of making shoots and/or roots.

D) cell differentiation.

Suppose that the four species of finches shown at the top of the picture above, are all released onto an island in the middle of the ocean. The only species of plant is the betel palm, shown below. The betel palm produces large nuts with a tough outer husk. According to the law of natural selection, which species of finch probably has the greatest chance to survive over the long term? A) finch species 2 B) finch species 3 C) finch species 4 D) finch species 1 Finch species 1 has the largest and strongest beak. The beak of this finch will help it eat the large nut.

D) finch species 1

Evidence for evolution includes the presence of _______________________, which are similar structures shared by different species. A) gradual structures B) vestigial structures C) integrated structures D) homologous structures Homologous structures are those features or organs that are shared by very different species (ex. forelimbs bones in bats and penguins).

D) homologous structures

The bones in the front limbs of many mammals are similar in their structure and arrangement. What term is used to describe physical similarities between related species that indicates a common ancestry? A) vestigial organs B) convergent anatomy C) embryonic parallels D) homologous structures Similar body structures among closely related species are known as homologous structures. Homologous structures are considered to be evidence of a shared ancestry.

D) homologous structures

The wing of a bird and the leg of a horse are very different looking structures. Although they look different, bird wings and horse legs are very similar in the arrangement of the bones that make up the limb. Which term is used by scientists to describe structures that look different on the outside but are actually similar in construction and develop from the same embryonic tissues? A) common descent B) ancillary anatomy C) vestigial structures D) homologous structures Structures of organisms that may look different but have strong similarities in construction and come from the same embryonic tissues are called homologous structures.

D) homologous structures

In 1809, Lamarck developed one of the first theories of evolution called the A) independent assortment. B) survival of the fittest. C) inheritance of variations. D) inheritance of acquired characteristics. Inheritance of acquired characteristics is the false idea that organisms change in order to meet the needs of their environment.

D) inheritance of acquired characteristics.

Fifty years ago, bed bugs were nearly eliminated in the United States by using of pesticides like DDT. Today bed bugs are back in beds and theaters. DDT is no longer used due to environmental issues. Pyrethrums are currently the top choice for bed bug infestations. Pyrethrums are especially useful to us because they generally have a stronger effect on bugs than on humans and animals. Some bed bugs had mutations in their genetic code which allowed them to survive the chemical pesticide and they produced chemically resistant offspring. How can this be explained? A) mutations were planned out by the bugs B) bed bugs chose other bugs to partner with who had the mutation C) bed bugs chose other bugs to partner with who had no mutations D) mutations involved the genetic variation of the bugs are random The mutations involved the genetic variation of the bugs are random. Some variations are favorable for the organisms environment and some variations are not.

D) mutations involved the genetic variation of the bugs are random

If scientists wanted to learn more about evolutionary history, they would study all but one of these molecules. Which biological molecule would NOT offer much information about the history of life? A) DNA B) proteins C) nucleic acids D) phospholipids The sequence or arrangement of phospholipids is not determined by the genetic history of an organism. Phospholipids are chemically similar in all cells.

D) phospholipids

Which theory of how evolution occurs would argue that all of the oak species in Georgia appeared suddenly from one common ancestor, over a short period of time, due to some extreme environmental changes, and that since that time, they have not changed much? A) gradualism B) microevolution C) macroevolution D) punctuated equilibrium Punctuated equilibrium. This theory of how evolution works, holds that environmental extremes cause rapid evolution, followed by long periods, when the environment remains relatively stable and the organisms in it do not change much.

D) punctuated equilibrium

Fifty years ago, bed bugs were nearly eliminated in the United States by using of pesticides like DDT. Today bed bugs are back in beds and theaters. DDT is no longer used due to environmental issues. Pyrethrums are currently the top choice for bed bug infestations. Pyrethrums are especially useful to us because they generally have a stronger effect on bugs than on humans and animals. However, bed bugs have become resistant to even this chemical pesticide. What happened that allowed the bug population to increase? A) the chemicals used currently are weaker B) the chemicals no longer can penetrate bed bugs brains C) the bed bugs of today are exactly the same as the bed bugs of fifty years ago D) the bed bugs that survived the DDT years ago, reproduced new generations of chemical resistant offspring The bed bug population has increased because the bed bugs that survived the DDT years ago, reproduced new generations of chemical resistant offspring.

D) the bed bugs that survived the DDT years ago, reproduced new generations of chemical resistant offspring

Darwin theorized that the finches on the Galapagos Islands were related because the finches A) had the same size beaks. B) ate the same kind of food. C) sang the same kind of song. D) were the same size and color. The finches shared many physical characteristics. They were the same size and color. This evidence led Darwin to conclude that they all evolved from the same species. Other factors such asgenetic similarities are used to determine if species are closely related.

D) were the same size and color.