TEAS Life Science 12,13, 15

What is natural selection?

The process where organisms with traits better suited to their environment survive and reproduce more

What is an adaptation?

An inherited trait that increases an organism's ability to survive in its environment

What is a mutation?

A change in DNA sequence — the original source of all genetic variation

What is genetic variation?

Differences in alleles within a population — necessary for natural selection to work

What is fitness in biology?

An organism's ability to survive and reproduce in its environment

What is speciation?

When one species splits into two separate species over time due to isolation and different selective pressures

What is the fossil record as evidence for evolution?

Preserved remains of organisms showing how life has changed over time

What are homologous structures?

Same structure, different function in different species — evidence of common ancestry — example human arm and whale flipper

What are vestigial structures?

Structures with no current function that were useful in ancestors — example the human tailbone

What is the classification system order from broadest to most specific?

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

What is the mnemonic for classification?

Dear King Philip Came Over For Good Soup

What are the six kingdoms?

Bacteria, Archaea, Protista, Fungi, Plantae, Animalia

What is binomial nomenclature?

The two-part scientific naming system using Genus and species — always italicized, genus capitalized, species lowercase

Give an example of binomial nomenclature

Homo sapiens — Homo is the genus, sapiens is the species

What are the levels of biological organization beyond organism?

Population — all members of one species in an area, Community — all species in an area, Ecosystem — community plus its physical environment, Biosphere — all ecosystems on Earth

What is a food chain?

Shows the flow of energy from producers to consumers — Producer → Primary consumer → Secondary consumer → Tertiary consumer

What are producers?

Organisms that make their own food through photosynthesis — plants and algae

What are consumers?

Organisms that eat other organisms for energy

What are decomposers?

Organisms that break down dead matter and recycle nutrients — fungi and bacteria

What is the 10% rule in energy flow?

Only about 10% of energy transfers from one trophic level to the next — the rest is lost as heat