Bio Ch. 22 Evolution
how long ago did one single supercontinent, stretching from pole to pole, exist on earth?
250 million years ago
life began on Earth approximately ________ years ago.
3.8 billion years ago
pharyngeal slits in embryos can be used to demonstrate ________.
A common vertebral ancestral line
A particularly harsh winter kills off 90% of the individuals in a population of reindeer. The resulting populations gene pool is no longer representative of the original gene pool. This is an example of ________.
The bottleneck effect
in the year 2317 a group of human pioneers decide to colonize Mars. The distance between Mars and Earth prevents the possibility of new members joining the colony or the members of the colony interbreeding with humans on earth. This situation is an example of
The founder effect
The loss of many marsupials from South America was the result of
The migration of placental mammals from North America into South America, where they outcompeted the marsupials
The bacteria initially persist in the predatory cell because
The predatory cell is unable to digest the bacteria.
which of the following best describes evolutionary "fitness"?
ability to survive and reproduce relative to other members of a population
________ refers to the development of many new species from a single ancestor in a relatively short time.
adaptive radiation
A bird's wing and an insect's wing both evolved for flight, but they evolved from entirely different structures. These wings are examples of
analogous
first in the lineage in the development of humans; ape-like anatomy; sexual dimorphism; walked upright
australopithecus afarensis
which of the following have coexisted with modern Homo sapiens?
both homo neanderthalensis and Homo floresiensis
after a long period of coevolution, the photosynthetic bacteria consumed by the predatory cell became the cellular organelle known as the
chloroplast
vestigial structures, homologous structures, and biochemical similarities all provide evidence of
descent from a common ancestor
cytochrome c oxidase is an enzyme found in countless organisms across the living world. Studying this enzyme is valuable for our understanding of evolution because ________.
differences in cytochrome c oxidase can be used to demonstrate the time frame of divergence between different branches of the evolutionary tree
The evolution of populations due to chance is
genetic drift
The amino acid sequence of the protein cytochrome c is compared between three different species: gray whale, hippo, and elephant. It is found that gray whales differ from hippo by five amino acids, hippo differs from elephant by 12 amino acids, and gray whale differs from elephant by 30 amino acids. From these data, you could hypothesize that ________.
gray whales are most closely related to hippos
decline in sexual dimorphism; formation of hunting and gathering groups that shared food; first in the human line to move from Africa to Europe and Asia
homo erectus
first in the human line to use tools; had a diet that included meat instead of a vegetarian diet
homo habilis
used a spoken language; large brain size; human like anatomy
homo sapiens
The discovery of the new species, homo floresiensis, created controversy among anthropologists because
it had long been assumed that a large brain size was required for sophisticated tool making and complex social organizations
after a long period of coevolution, the aerobic bacterium consumed by the predatory cell became the cellular organelle known as the
mitochondrion
Which of the following agents of microevolution can create new genetic information in a population?
mutation
The most important force in evolution is
natural selection
which of the following agents of microevolution consistently leads to adaptation of organisms to their environment?
natural selection
which of the following can affect the make up of the gene pool within a population?
natural selection, mutation, migration of individuals into or out of a population
The first step in the development of living organisms was the formation of
organic molecules from gases in the atmosphere
Sexual selection is based on
phenotype
which of the following milestones happened first?
photosynthesis evolved
oxygen in earth's atmosphere resulted from ________.
photosynthetic organisms
which one of the following taxonomic categories is defined as a group of organisms that are capable of interbreeding and producing fertile offspring?
species
True or false? With the advent of photosynthesis and the subsequent production of oxygen by photosynthetic organisms, most of the anaerobic organisms present on earth became extinct because oxygen was actually toxic to these organisms.
true
examination of the skeleton of whales shows bones similar to the human pelvic girdle. In whales, these bones would be considered ________.
vestigial structures
The largest mass extinction ever to occur on earth ________.
was the Permian-Triassic extinction