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The most accurate meaning of the term evolution is
The basic difference between a prokaryotic cell and a eukaryotic cell is that the eukaryotic cell
possesses membrane-bound organelles
The studies of which geologist indicated a much greater age of the Earth than had veeb proposed before?
The first self-replicating molecules were probably
Who first disproved the "maggots from meat" hypothesis?
Who disproved the "broth to microorganisms" hypothesis?
The earliest fossils resemble modern
Where did most of the oxygen in our atmosphere come from?
_________ may have evolved from aerobic bacteria and __________ may have evolved from cyanobacteria that were engulfed by predatory prokaryotic cells
About 530 million years ago, fish became the dominant predators of the sea because of the evolution of
The first land plants were restricted to moist, marshy environments because of
reproductive cell requirements
__________ eliminated the need for water in plant reproduction
The earlist group of land plants whose reproduction did not require water for swimming sperm were the...
The fossil evidence indicates that amphibians evolved from...
What group of vertebrates was the first to evolve a waterproof egg?
The first terrestrial animals were
Primitive fish called ______ were probably the ancestors of both modern bony fish and _____
Birds and mammals have similar forelimbs, four-chambered hearts, and a notochord at some stage of development. These similarities are BEST explained by...
a common ancestry
A bat's wing and a sheep's front leg are ______ structures
The human appendix is an example of a(n)
The biological species concept cannot be applied to
When there is no gene flow into a population, the population is said to be
Darwin was influenced by an essay on the limits to human population growth written by
The theory that "organisms can modify their bodies through use or disuse of parts, and these modifications can be passed onto their offspring" was formulated by
The wings of insects and bats are _________ structures
Squirrels separated by canyon. If no longer the same species, it's a result of
Blue-footed boobies need specific courtship dance. What keeps the mating within the species?
Moss species produce gametes at different times of year. Example of _________ isolating mechanism.
Fig wasps live and mate within same species of fig. This is...
Inability of sperm to fertilize eggs of different species is called...
Horses and donkeys mate to make mules. Mules are infertile. Called...
When hybrid organisms don't live long
Two populations become geographically separated from each other and then genetically diverge
When a species invades a new habitat and evolves rapidly into several new species to better exploit new resources, what has occurred?
The hominids originally evolved in
What is the significance of upright walking?
It frees the hands for gathering and carrying food
The hobbit-sized hominid whose fossilized remains were recently discovered on a remote oceanic island was a
segments of DNA
the assortment and interactions of species on Earth
The idea of uniformitarianism suggests what about the geological record and age of the Earth?
Natural processes occurring over long periods of time accounted for the thick layers of rock where fossils are found, rather than cataclysmic events
Which of the following pairs is most distantly related
bacteria and archaea
Which of the following would have prevented the development of conditions favorable for the evolution of life after Earth was formed?
unbound, or free, oxygen molecules
What chemicals were produced by Stanley Miller and other researchers in their experiments investigating the origin of life?
BOTH: amino acids and ATP AND short proteins and nucleotides
A likely group of organisms in which to look for cases of sympatric speciation would be
parasitic intestinal worms