Exam #4 Study Guide

According to this evolutionary tree, when did hominins branch away from the other apes?

5-7 mya

How is mitochondrial DNA inherited?

All mitochondrial DNA is inherited from the mother.

Which of the following best describes the source of your mitochondrial DNA?

All of my mitochondrial DNA was inherited from my mother.

When making sourdough bread, bakers use a combination of microorganisms to produce the sour flavor and to leaven the dough before baking. The organisms typically used to produce the lactic acid that give sourdough its distinctive flavor are very small rod-shaped prokaryotic organisms known generally as Lactobacilli. These microorganisms are from the kingdom ________. The other organisms that produce the leavening effect are nonphotosynthetic eukaryotes, have cell walls, absorb their nutrients from their environment, and (in this case) are very tolerant of acidic environments. These microorganisms are from the kingdom ________.

Bacteria; Fungi

Why might many new species form in the aftermath of a mass extinction?

Changed environments and reduced competition would provide opportunities for new adaptations.

Although it is costly to produce fruit, the large number of fruit-producing plant species attests to its success as an evolutionary adaptation. In what way is fruit production helpful to plants?

Consumers eating fruits also eat seeds that, when not digested, can be deposited far from the parent plant and increase the range of that plant species.

How is nuclear DNA inherited?

Fifty percent of nuclear DNA is inherited from the mother's ancestral line and 50 percent from the father's ancestral line.

Every year, environmental signals in Africa cause flycatchers to return to the Netherlands to breed. When they arrive, they depend on freshly hatched caterpillars for food. Global climate change has caused the caterpillars to hatch earlier in the Netherlands, but the environmental cues in Africa remain the same. Now, when the flycatchers return to the Netherlands the caterpillars are no longer available as a food source. Which of the following is most likely to happen to this species of flycatcher?

Flycatchers will adapt to environmental change if alleles that aid flycatchers in utilizing other food sources (besides caterpillars) are present.

Which of the following best describes the source of your nuclear DNA?

Half of my nuclear DNA was inherited from my mother and half from my father.

The correct two-word Latin, scientific name, for modern humans is

Homo sapiens.

You are camping in the south central United States when one evening you happen across an animal with several "armored" plates covering its back and shoulders. The plates are bony and separated by thin bands of flexible skin. The belly of this short-legged quadruped is covered with skin and soft fur. You also notice four young ones scurrying along with the adult. This animal most likely belongs to which class?

Mammalia

Examine the skulls shown in this figure. What can be said regarding trends in braincase size and teeth over time?

More recent hominin fossils have larger braincases and generally smaller, more humanlike teeth.

Which of the following is true with regard to mutations?

Mutations appear without regard to environmental pressures.

A mutation in a gene produces the identical protein to the original gene and therefore, an identical trait. Will evolution act upon this mutation?

No, because evolution acts upon phenotypes.

If your mitochondrial DNA was sequenced and compared to the sequence of mitochondrial DNA isolated from your mother's paternal grandmother (the mother of your mom's dad) would you expect to see a significant match to yours and why?

No, there would not be a significant match because my mitochondrial DNA was inherited from my mom who inherited it from her mom.

Jean-Baptiste Lamark proposed that populations evolve when traits acquired during the lifetime of a parent are passed down to offspring. What is wrong with this proposal?

Only changes in the DNA sequence of an organism can be inherited. Traits acquired throughout life generally do not involve DNA.

Which of the following is an example of gene flow?

Pollen from a population A plant lands on a population B plant.

Resolving the relationship between the various kingdoms has been challenging because species often resemble one another. For example, the kingdom ________ contains some organisms that are animal-like and others that are plantlike.

Protista

You are relaxing on the veranda of your beachfront rental on the Gulf of Mexico when you notice a small (about 5 inches long), green quadruped clinging to the ceiling. As it begins to run down the wall, you catch it and notice that it is covered with dry scales, has a long tail, and specialized toe pads that allow it to stick to surfaces. This animal most likely belongs to which class?

Reptilia

Which of the following is NOT an advantage of bipedalism in hominins?

Standing on two feet makes it easier to climb trees.

When researchers determined that the jawbone of an Italian Neanderthal dating to around 43-45 tya showed the presence of an intermediate chin and mitochondrial Neanderthal DNA, they hypothesized that the jawbone belonged to an individual who was the product of a mating between a modern human and a Neanderthal. Which of the following lines of evidence would also support this hypothesis?

The fossil would have both Neanderthal and Homo sapiens genomic DNA.

Which of the following is an example of a prezygotic barrier that can isolate two species living in the same geographic area?

The gametes of one species of orchid in a rainforest are unable to fuse with the gametes of another species of orchid in the same rainforest.

The mass extinction at the end of the Cretaceous period about 65 mya is believed to have been caused by a massive comet or asteroid smashing into what is now known as the Yucatan peninsula in the Gulf of Mexico. The debris arising from this impact would have blocked the Sun's rays from reaching the Earth. How would this cause a mass extinction?

With no sunlight, the plants would not be able to photosynthesize food for themselves, and they would die. Any animals that fed on those plants would also die, and any animals that would have eaten those animals would also now starve to death. This chain reaction would continue up the food chain.

A population of 8,250 mice occupies the sand dunes in a coastal area. A severe hurricane washes out several miles of sand dunes. As a result, only 50 mice remain. The population has experienced

a bottleneck.

Evolutionary trees are based on

a set of shared characteristics believed to have arisen in a common ancestor.

Evolutionary trees are continually revised by scientists as new information becomes available from various sources such as

additional, similar fossils found in relation to the geological time period.

Adaptive evolution allows species to

adjust to environmental changes.

All are benefits of prokaryotes EXCEPT

all are benefits of prokaryotes

The development of upright posture in hominins is likely

an adaptation for living on the ground instead of in the trees.

The most recent mass extinction, which occurred during the Cretaceous period, may have been caused by

an asteroid hitting Earth.

Convergent evolution produces

analogous characteristics.

According to the tree below, which of the following combinations of organisms are most closely related?

animals and fungi

Eggs provide

both nuclear and mitochondrial DNA to the offspring cell.

Speciation

can result from geographic isolation.

A prokaryote that gets its carbon from CO2 and its energy from chemicals would be known as a

chemoautotroph

The rough-skinned newt produces one of the most potent toxins on the planet. Scientists in Oregon have found that as newts evolve to produce a more deadly toxin, their primary predator, the garter snake, evolves ways to resist the toxin. This is an example of

coevolution of predator and prey.

In many predator-prey relationships, evolutionary change in the prey will result in evolutionary change in the predator, a phenomenon known as

coevolution.

Evolutionary tree diagrams representing the relationships between various organisms can be drawn only when those organisms share a

common ancestor.

Two unrelated species evolving to look more similar due to environmental pressures is called

convergent evolution.

Two different species may have similar features because of

descent from a common ancestor.

Genetic variation is based on

differences in genotypes between the individuals in a population.

The red-breasted nuthatch and the white-breasted nuthatch are similar in appearance and, in many regions of the United States, their ranges overlap. The two organisms do not interbreed. Based on this information, red-breasted and white-breasted nuthatches are

different species.

Convergent evolution occurs when natural selection causes distantly related organisms to

evolve similar structures in response to similar environmental challenges.

Both insects and humans evolved jointed legs to allow locomotion on land. These structures are considered analogous because insects and humans

evolved from different ancestors.

Although populations of North American apple maggot flies are not geographically isolated, they appear to be in the process of diverging into two new species. Which of the following could be causing speciation between two populations in the lack of geographic isolation?

feeding on two different types of food

Populations within a species are connected by

gene flow.

The following image is an example of

gene flow.

While on a camping trip, you collect a white tadpole from a pond and take it home. The tadpole develops into a white bullfrog. When the frog gets too big, you release it into a local pond. The next year, several white bullfrogs are observed in the pond. This is an example of

gene flow.

Which of the following categories of the Linnaean hierarchy would include the most closely related organisms?

genus

When a brightly colored guppy population is placed in an area containing many predators, the population changes in only a few generations to one containing only guppies with drab, dull colors that blend into their environment. This is an example of how natural selection can

improve the match between guppies and their environment.

The Cambrian explosion

increased the diversity of animal life on Earth

The first vertebrates to evolve lacked jaws and had skeletons made from a strong flexible tissue called cartilage. The lamprey is a modern example of this ancient group of vertebrates known as

jawless fishes

Which of the following groupings of animals are most closely related to each other?

lemurs, chimps, humans

Which of the following could NOT be used to describe humans?

marsupial

For which of the following would a mountain range most likely represent a geographic barrier that would block gene flow?

mice

For a population to evolve, there must be genetic differences between organisms in that population. These differences arise by

mutation.

Quarum sensing is the way some prokaryotes can sense

other prokaryotes

Which of the following categories of the Linnaean hierarchy would include the broadest range of related organisms?

phylum

Some prokaryotes that live in "extreme" environments are known as "halophytes." The prefix halo means

salt

Individuals of the same species generally

share many common physical and behavioral characteristics.

If you are watching a fictional movie set in a land dominated by flowering plants, plus advancing and retreating glaciers and a cast that includes a human, a wooly mammoth, a saber-toothed cat, and dinosaurs, which characters would be most out of place in the setting according to the geological time line of life on Earth?

the dinosaurs

Which of the following events occurred between each branch on an evolutionary tree?

the evolution of a new derived feature

Gymnosperms and angiosperms are believed to be more closely related to one another than the other major plant groups because

they provide their embryos with stored food that can support growth before photosynthesis begins.

At the base of the evolutionary tree of all life is the

universal ancestor.

The current classification system used by biologists is

updated and revised whenever new information becomes available.

During the Devonian period, plants evolved which of the following key innovations to overcome the harsh, dry conditions of life on land and flourish?

waterproof cuticle, vascular systems, structural support tissues, leaves, roots, seeds, and specialized reproductive structures