Evolution and Adaptation Flashcards
What is ecology?
The study of the interrelationships among plants and animals and microorganisms and their interactions with the environment.
What is environment?
Literally means surroundings. From french word environs.
What are the components of an environment?
Chemical, physical and biological.
Does an environment have boundaries?
Strictly speaking the environment has no boundaries, but in practice it is common to restrict the discussion to a particular region.
What is an organism?
An individual that has all the characteristics of life (cells to organ systems, capable of metabolism) and has the same genetic information in all its cells.
What is a population?
A group of individuals of the same species living in the same environment and actively interbreeding.
What is a community?
A number of populations living and interacting together in the same environment.
What is a ecosystem?
The community plus its environment and the community members dependence upon each other and the abiotic components. The scale can vary considerably.
Examples of a ecosystem?
pond, field, forest, desert, gastrointestinal system of animals, etc
What is a biome?
Major type of ecosystem.
Types of terrestrial biomes?
Tundra
Grasslands
Desert
Tropical rain forests, etc
What determines the type of ecosystem that will develop into specific terrestrial biomes?
The amount of precipitation.
Types of biome with percipitation
Biome Precipitation Desert 0 to 25 cm/year Grasslands 25 to 75 cm/year Dry forest 75 to 125 cm/year Tropical rain forests 125 or more cm/yr
What is a habitat?
The range of environments in which a species lives.
What is a niche?
A unique functional position each type of species occupies in an ecosystem.
What is evolution?
The process of genetic change by which species adapt to their environment or develop new ways of coping environmental stress.
What is is the most fundamental organizing principle in biology?
The theory of evolution.
Modern understanding of evolution is based on what?
Genetic theory.
Evolution can be described based on the understanding that individuals in a population vary in numerous traits. What are these trait?
Morphological – related to structure (ex. height)
Biochemical – ex. ability to produce certain compounds
Behavioral – ex. aggressiveness in dogs
What are the two mechanisms of evolution that act in combination?
Random variation and natural selection.
What are random variations?
Are random mutations in the genetic code, and sorting and recombination of genetic material that occurs during meiosis.
What are mutations cause by?
Errors in the biochemical processes of reproduction or by damage from chemical or physical agents (ex. ionizing radiation).
What are adaptions?
Favorable traits which tend to increase the fitness of a population to an environment.
Before molecular biology evolution was supported by what three types of evidence?
- Fossil record.
- Comparisons between the structure and function of different species.
- Analyzing the geographical distribution of existing species.
What is a genetic drift?
Random changes in traits occurring in a population.
