B15: Genetics and evolution Flashcards
what is evolution
change in the inherited characteristics of a population over time through natural selection, which may result in a new species
who first proposed the theory of evolution by natural selection
Charles Darwin
what is the theory of evolution by natural selection
all species of living things evolved from a common ancestor that developed billions of years ago
describe Lamarck’s idea of inheritance
organisms change over their lifetime and these characteristics can be inherited
why was the theory of evolution by natural selection controversial
- challenged the idea that God made all of earth’s animals and plants
- insufficient evidence at the time
- genes, inheritance, and variation were not understood
what is speciation
gradual formation of a new species as a result of evolution
what evidence supports the theory of evolution
- parents pass on their characteristics to offspring in genes
- fossil record evidence
- evolution of antibiotic resistance
what did mendel discover through breeding experiments on plants
inheritance of characteristics is determined by units (genes) passed on unchanged offspring
what are fossils
remains of organisms from millions of years ago, found in rocks
how might fossils be formed
- parts of an organism do not decay because the conditions needed for decay are absent
- traces of organisms are preserved
- parts of an organism are replaced by minerals
what are the benefits of the fossil record
can learn how species changed and life developed on earth, and can track track the movement of species around the world
what are the problems with the fossil record
- many early organism were soft-bodied so left few fossils
- gaps in the fossil record as not all fossils have been found and some have been destroyed
what is extinction
no individuals of a species are still alive
what is the binomial system
naming of organisms by their genus and species
what classification system did Carl Woese introduce
three-domain system of Archea, Bacteria, and Eukaryota