Natural selection must be acting on the population
Genetic drift as an evolutionary factor is
Greater in a population with small numbers than in a population with large numbers.
The ultimate origin of genetic variation is
Due to various causes, including DDT poisoning, the population size of whooping cranes was reduced to a/b a dozen. The pop size has since rebounded, and there are now hundreds of whooping cranes. Which would you expect NOT to see?
Very low levels of genetic variation
Which of the following processes result in adaptation?
Natural selection works directly on?
the phenotype and indirectly on the genotype
What is the differential reproductive success of individuals w/ particular variations?
How do biologists explain brightly colored extreme features on a peacock that cannot be explained by natural selection?
A population in which allele and genotype frequencies do not change overtime is said to be in?
When phenotypes are favored at one extreme of a phenotypic distribution __________ selection occurs
In order to be in genetic equilibrium a population must
be very large
What evolutionary advantage is provided by sexual reproduction?
Increased genetic variation
The oldest fossil remains of members of our genus, homo, suggest that early relatives of humans live
In dry African savannas, where they ate roots, bulbs, tubers, and animals
What hominid is the oldest?
The first species in the genus Homo known to have migrated from Africa was?
Homo sapiens most likely evolved in?
What is the world population of humans today?
About 6.5 billion
Races, as conventionally conceived...
Are sociological categories
Skin pigmentation is the most common criterion for distinguishing human races. This is not valid for categorizing humans b/c/?
Except in the case of albinism, human skin color is a polygenic trait.
A major trend observed in the evolution of primates generally, and in hominids particularly is?
An increase in the size of the cerebrum
The white blood cells of an individual to cells lining his/her digestive tract, and the 2 cell types perform very diff functions. This is b/c?
They are present in different parts of the body.
In adult humans, the largest number of multipotent stem cells is found in the bone marrow. These adult stem cells can differentiate into?
Most, but not all cell types and tissues
What is homeostasis?
The maintenance of a relatively stable internal environment
Which of the following is the best example of negative feedback?
An increase in body temperature resulting from shivering
Neurons that transmit information to the central nervous system are?
What are the divisions of the peripheral nervous system?
Sensory and Motor
Bundles of wiring that connect neurons
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