Chapter 2: Biology, Genetics & Evolution Flashcards
Genus (general)
In the system of plant and animal classification, a group of like species.
Species
The smallest working units in biological classificatory systems; reproductively isolated populations or groups of populations capable of interbreeding to produce fertile offspring.
Natural selection
The evolutionary process through which factors in the environment exert pressure, favoring some individuals over others to produce the next generation.
genes
The portions of DNA molecules that direct the synthesis of specific proteins.
DNA (deoxyribonucleic acid)
The genetic material consisting of a complex molecule whose base structure directs the synthesis of proteins.
alleles
Alternate forms of a single gene.
Phenotype
The observable characteristic of an organism that may or may not reflect a particular genotype due to the variable expression of dominant and recessive alleles.
Hemoglobin
The protein that carries oxygen in red blood cells.
Population
In biology, a group of similar individuals that can and do interbreed.
Gene pool
All the genetic variants possessed by members of a population.
Evolution
The changes in allele frequencies in populations; also known as microevolution.
Hardy-Weinburg principle
The concept that demonstrates algebraically that the percentages of individuals that are homozygous for the dominant allele, homozygous for the recessive allele, and heterozygous should remain constant from one generation to the next, provided that certain specified conditions are met.
mutation
The change alteration of genetic material that produces new variation.
genetic drift
The chance fluctuations of allele frequencies in the gene pool of a population.
gene flow
The introduction of alleles from the gene pool of one population into that of another.
adaptation
A series of beneficial adjustments to a particular environment.
Reproductive success
The relative production of fertile offspring by a genotype. In practical terms, the number of offspring produced by individual members of a population is tallied and compared to that of others.
sickle-cell anemia
An inherited form of anemia produced by a mutation in the hemoglobin protein that causes the red blood cells to assume a sickle shape.
punctuated equilibria
A model of macroevolutionary change that suggests evolution occurs via long periods of stability or stasis punctuated by periods of rapid change.
Charles Darwin (1809-1882)
natural selection
Jane Goodall
Primatologist who has studied chimpanzees for nearly 45 years. The knowledge she has amassed reveals striking similarities with our species.
Dmanisi, Georgia
One of the many locations where fossils of Homo erectus have been located, and now known to have inhabited 1.8 mya.
Lake Turkana, Kenya
The location where Richard Leakey discovered a well-known fossil known as KNM ER 1470, 1.9 mya; these deposits like those at Olduvai, also contain crude stone tools. This fossil’s skull is more modern in appearance than any Australopithecus skull and has a cranial capacity of 752 cc.
Hadar, Ethiopia
Also known as Afar, one of the many locations where Australopithecus fossils have been discovered.
Berhane Asfaw
world-renowned paleoanthropologist leading major expeditions in Ethiopia.
Orrorin tugenensis
6 million year old fossils discovered in Kenya by French and British researchers Brigitte Senut and Martin Pickford, reported as human ancestors, nicknamed the “Millenium Man”. The bones recovered demonstrate possible but not definite bipedalism.
